When Your Child With a Developmental Disability Turns 18: What Changes and What Parents Can Do

You have spent your child’s whole life being their voice, their advocate, and their safety net. That role does not have to end at 18, though the way it works legally does change.

The day your child with a developmental disability turns 18, California law treats them as an adult, even when they still need your help with decisions every single day. A Limited Conservatorship of the Person can give you back the specific legal authority your child still needs you to have, while preserving as much of their independence as possible.

On this page:

• What changes when your child turns 18
• Your options at 18, and where they fall short
• What a limited conservatorship is
• The seven powers a court can grant
• Will it limit or single out my child?
• Conservatorship of the person versus the estate
• Who else is involved in the case
• When to start, and why 17 matters
• How it fits into a complete special needs plan
• How our process works
• Do we need an attorney to file?
• What to do this week

What changes when my child turns 18?

Until your child turns 18, you make their decisions automatically. The morning they become a legal adult, that authority ends by law, even when your child still needs help to make those decisions safely. Without the appropriate legal authority or decision-making arrangement in place, here is what can happen at the moment you most need to act:

• A hospital will not share information or take your direction in an emergency
• A school or regional center will not include you in the meeting
• A benefits office makes a decision without you
• Someone talks your child into a contract, a credit card, or a purchase

None of this means your child stops needing you. It means the law needs you to hold the right authority, on paper, before the moment you have to use it.

What are the options once my child is 18?

The right answer depends on your young adult: what they can manage on their own, and where they still need someone with legal standing to step in. Here is what is available, and how each one tends to work for a young adult with a significant developmental disability.

• Supported decision-making lets trusted people help your young adult understand choices and decide for themselves. It fits when your young adult can make and communicate their own decisions. It carries no legal authority, so a hospital or school is not required to honor it.
• Powers of attorney and an advance health care directive only work if your young adult has the legal capacity to understand and sign them. Many young adults with a significant developmental disability do not, and a document signed without that capacity can be challenged later.
• A representative payee lets a parent manage Social Security benefits like SSI. It covers those benefits and nothing else, so it gives you no authority over medical, educational, or residential decisions.
• A limited conservatorship asks the court to grant authority in the specific areas where your young adult needs help, and leaves every other right with them.

If your young adult handles most decisions independently, the less restrictive tools may be enough. But for a young adult with a significant developmental disability who needs ongoing help with medical, educational, and daily-life decisions, those tools usually do not go far enough. In our experience, a limited conservatorship is what most of these families need. Without a court order, parents may otherwise have no legal authority in the areas where their young adult still needs help.

Two situations come up most often where a limited conservatorship may not be the right fit. A young adult who can understand, direct, and communicate their own decisions may do well with the less restrictive tools. And a limited conservatorship covers developmental disabilities specifically, so if your adult child’s needs come from a psychiatric condition such as schizophrenia, that is handled through a different kind of conservatorship. We can walk through the options with you and help you figure out what makes the most sense for your child.

What is a Limited Conservatorship?

A Limited Conservatorship is a court arrangement in which a judge appoints a responsible person (the conservator, usually a parent) to help an adult with a developmental disability in the specific areas where they still need decision-making support. It is designed for adults whose disability began before age 18, such as autism, Down syndrome, cerebral palsy, or an intellectual disability.

It is called “limited” on purpose: the court grants the specific powers your child needs and leaves every other decision with them. You get clear legal authority in the areas where your child needs support, and your child keeps their independence everywhere else.

The conservatorship is a tool, not the goal. The goal is what it makes possible: guiding, protecting, and supporting your child so they can live the fullest life they can.

What are the seven powers, and what will the court actually grant?

A limited conservator can ask the court for up to seven powers:

1. Decide where the conservatee lives
2. Access their confidential records
3. Consent to or withhold consent to marriage
4. Enter into contracts on their behalf
5. Give or withhold medical consent
6. Decide their social and sexual contacts and relationships
7. Make educational decisions

In everyday terms, these are what let you keep showing up: sitting in on the doctor’s appointment, staying in the room for IEP and regional center meetings, and helping decide where your child lives and how they are cared for.

In our experience, the regional center supports the petition in most cases, and its recommendation carries real weight. The court still decides which powers are necessary, and in the cases we handle it generally grants what is requested and supported by the facts.

What gets granted is county-dependent. Orange County often grants five of the seven in standard cases: residence, contracts, medical decisions, access to confidential records, and education. Marriage and social and sexual relationships need a separate petition and more proof, and for many families those two powers are not necessary for the support they are seeking. Los Angeles County more commonly grants all seven when they are properly requested and supported by the facts.

After the hearing and some follow-up paperwork, you receive the Letters of Conservatorship, which list the exact powers granted. The Letters are what you show doctors, schools, regional centers, and agencies so they can recognize your authority in the areas the court approved.

Will a conservatorship limit my child or single them out?

This is one of the biggest worries parents bring to us. They wonder whether their young adult will lose independence, feel diminished, or carry a label they did not choose.

In practice, a limited conservatorship maintains the status quo. Day to day, family life looks much the same. The routines and the support do not suddenly change. What changes is the legal framework: the court gives you authority in the specific areas it approves.

In our experience, families more often describe relief than loss once that authority is in place. It lets you keep making sure your young adult has the best quality of life you can give them. And many young adults want that support from their parents.

There is a practical side too. Once your child turns 18, hospitals, schools, regional centers, benefits offices, and other providers may not be able to rely on a parent’s direction without legal authority. “I am their parent” is no longer enough by itself.

When a limited conservatorship is the right fit, that legal authority helps keep you in the room when your child still needs you there.

Does my child need a conservatorship of the estate too?

Most families asking about help with personal, medical, educational, and daily-life decisions are asking about a Conservatorship of the Person, not the Estate. There are two kinds of limited conservatorships:

• Of the Person: personal and daily-life decisions. This is what most families need.
• Of the Estate: financial matters, generally needed only if your child has assets that are not held in a special needs trust, such as an inheritance or a lawsuit settlement.

Benefits like SSI usually do not require an estate conservatorship on their own. A parent can serve as the Social Security representative payee and manage those benefits directly.

Many families pair a conservatorship of the person with a special needs trust. The conservatorship handles decision-making. The trust holds and manages family resources while helping preserve needs-based benefits.

Who else is involved in a Limited Conservatorship case?

A limited conservatorship is not just you and the judge. Several people look at your young adult’s situation before the court decides, and knowing who they are ahead of time makes the process feel far less unfamiliar.

• Your regional center. The regional center prepares a report for the court on whether it supports the conservatorship and which powers it believes fit your young adult’s needs. The court uses that report as part of its own analysis. If your child is not already a regional center consumer, the court will often order an assessment first.
• An attorney for your young adult. The court appoints a separate attorney to represent your young adult’s own interests. In Orange County that is generally the public defender’s office. In Los Angeles County it is generally a private attorney appointed by the court.
• Your young adult’s doctor. In most cases the doctor completes an assessment and the supporting paperwork the court needs, describing your young adult’s condition and the areas where they need help.
• The court investigator. The court sends an investigator to meet with your young adult, explain their rights, and report back. They meet with you as well, to understand your family’s situation.

Each person has a different role. The regional center and the court investigator provide information and recommendations, your young adult’s attorney advocates for your young adult’s wishes, and the judge decides what authority is appropriate. In our experience, this is not an adversarial process. Everyone understands how hard the situation is, and everyone is looking at the same question you are: what support does this young adult actually need?

When should we start?

When your child is 17. Court hearings are scheduled months out, and the timelines shift with court availability. As of mid-2026, Orange County hearings are being set roughly eight to nine months after filing, and Los Angeles County is sooner, roughly five to six months. Starting at 17, whatever county you are in, gets the petition on file and heard as close to the 18th birthday as possible.

The order cannot take effect until your child turns 18, so the goal is to be filed and ready, not rushed. If the hearing falls after the birthday, that is common and usually not a problem, and practical measures may help reduce disruption in the meantime.

And if your child is already 18 or older? You have not missed your chance. The process is the same, and starting now closes the gap sooner.

How does a Limited Conservatorship fit into a complete special needs plan?

The hardest question most parents carry is not about age 18. It is this: who looks after my child when I no longer can?

A conservatorship answers today. A complete plan looks further ahead, and it brings three things together:

• The right people, with the authority to act. The Limited Conservatorship gives you authority in the areas the court approves, and you can nominate a successor to provide continuity later.
• The right resources, coordinated so they reach the plan. A special needs trust holds and manages money for your child while helping preserve the benefits they rely on, like SSI and Medi-Cal.
• The right instructions, written down. A Memo of Intent records the routines, preferences, medical history, and hopes that no legal document captures, so whoever steps in actually knows your child.

One handles decisions, one handles money and benefits, and one makes sure the people who step in know your child. The conservatorship works best as part of one coordinated family plan: your child’s trust, your own estate planning, and the decision-makers all pointing the same direction. Our guide to special needs trusts in California walks through the resources side of that plan.

How our Limited Conservatorship process works

We handle the legal and procedural work so your family can stay focused on your young adult and the support they need:

1. Determine the right level of support. We learn what your young adult can do independently, where help is needed, and whether less restrictive options are sufficient.
2. Prepare the case for the correct county. We prepare the petition, notices, supporting information, proposed powers, and court documents around the process used in Orange County or Los Angeles County.
3. Complete the process and coordinate the larger plan. We guide you through the hearing, obtain the Letters of Conservatorship, and coordinate the result with the special needs trust and future decision-makers.

Do we need an attorney, or can we file this ourselves?

You can file a Limited Conservatorship yourself, and the courts provide self-help resources. But this is not a form packet. It is a court process with a petition, legal notices, a court investigator’s review, regional center questions, a required conservator training, proposed orders, and the post-hearing Letters. Each step has to line up before the next one works.

If a notice, service requirement, proposed order, or supporting document is incomplete, the court may continue the hearing, often for months, at exactly the moment your child is aging into adulthood. Orange County and Los Angeles County also handle parts of the process differently.

We prepare each case for the county where it will be heard, guide you through the hearing, and complete the follow-up needed to obtain the Letters. Working with a limited conservatorship attorney can reduce the risk of losing months to an avoidable mistake. We handle Limited Conservatorships for a clear flat fee, quoted in writing before we begin.

What to do this week

You do not need to know which legal option is right before you begin. Write down two things:

1. Which decisions your young adult already handles on their own
2. Which medical, educational, financial, or daily-life decisions still need your help

Then note the date of their 18th birthday. Those three pieces give us the starting point for evaluating the options and mapping the court timeline.

Your child may still need you past 18, and California law has ways to keep your support in place. If your child is 16 or 17, this is the season to act: one conversation can put the whole timeline on the calendar.

Let’s put the right support in place before your child turns 18. We will look at what your young adult can do independently, where support is still needed, and whether a limited conservatorship or a less restrictive arrangement is the right fit. If a conservatorship is appropriate, we prepare the case and guide your family through the court process.

If your child is already 18, the process is the same. Starting now closes the gap sooner. When you are ready, schedule an Initial Planning Session or call (949) 718-0420.

Laura Meier, Esq., Founder, Meier Law Firm · Newport Beach, California · Last reviewed August 2026