CA Prob Code Section 15404

(a)

If the settlor and all beneficiaries of a trust consent, they may compel the modification or termination of the trust.

(b)

If any beneficiary does not consent to the modification or termination of the trust, upon petition to the court, the other beneficiaries, with the consent of the settlor, may compel a modification or a partial termination of the trust if the interests of the beneficiaries who do not consent are not substantially impaired.

(c)

If the trust provides for the disposition of principal to a class of persons described only as “heirs” or “next of kin” of the settlor, or using other words that describe the class of all persons who would take under the rules of intestacy, the court may limit the class of beneficiaries whose consent is needed to compel the modification or termination of the trust to the beneficiaries who are reasonably likely to take under the circumstances.