Minors and unborn beneficiaries cannot sign anything, so a petition of this kind normally requires the court to appoint a guardian ad litem to speak for those interests. That person's job is to protect the represented beneficiary, not to help the family close the deal, and a guardian ad litem who objects can end the matter. Prob. Code § 15804 supplies the other half of the mechanism: notice to a person who may represent and bind another is sufficient notice to the represented person, which is how unborn and unascertained interests get reached without an impossible search. There is also a tax dimension people overlook. When beneficiaries agree to move value from one of them to another, so that your sister gives up her remainder interest and you take the house now, that reshuffling can be treated as a gift from her to you, reportable and chargeable against her lifetime exemption. Sometimes a qualified disclaimer, filed within the deadline, does the job more cleanly than a modification. As for the statutes, Prob. Code § 15404 is the no-court route, settlor plus all beneficiaries in writing, and Prob. Code § 15403 is the petition route where all beneficiaries consent, with the court free to refuse if continuing the trust unmodified is necessary to carry out a material purpose unless the reason for the change outweighs that purpose.
Fixing or Changing a Trust · California
Can all the beneficiaries just agree to change the trust?
Sometimes, and everything turns on the word "all." Every consent route in California requires all of the beneficiaries, and "all" is almost always a larger group than the people sitting around the table talking about it. It includes the contingent remainder beneficiaries: the grandchildren who take only if your brother dies before distribution, the nieces who take if a whole branch of the family fails, the charity written in as a backstop taker in the last article of the document. It includes the beneficiary who has not spoken to anyone in nine years, and it includes people who have not been born yet. Families usually reach agreement first and count heads second, and the head count is where the plan comes apart. One holdout, one cousin nobody can locate, or one unborn class is enough to stop a consent modification cold, and no amount of agreement among the willing substitutes for the signature that is missing.
This page is general information about California law, not legal advice, and does not create an attorney-client relationship. Figures and deadlines change, and every family’s situation is different. Last reviewed August 2026.
Related Questions
The questions this one leads to.
Can an irrevocable trust be changed in California?
Yes, in defined circumstances. The three California routes to change an irrevocable trust, who has to sign each one, and when a judge has to approve it.
Read the answerDoes the trustee need court approval to change a trust?
Usually the trustee cannot change the trust at all. What a California trustee risks personally by bending the terms, and how a court order protects them.
Read the answerMy mother put her house in an irrevocable trust before she got sick — can we undo it?
Possibly. Whether a California irrevocable trust holding a parent's house can be undone depends on her capacity, the beneficiaries, and why it was created.
Read the answerNext Step
Ask Robert P. Bergman about your own facts.
The 15-minute Consultation is free. Bring the assessor’s notice, the trust, or just the question, and you will leave knowing which deadline applies to you.
Robert P. Bergman is one of less than 1% of California attorneys certified as a specialist by the State Bar.