California Code, Probate Code - PROB § 6522

(a) The probate homestead shall be selected out of the following property, giving first preference to the community and quasi-community property of, or property owned in common by, the decedent and the person entitled to have the homestead set apart:

(b) The probate homestead shall not be selected out of property the right to possession of which is vested in a third person unless the third person consents thereto. As used in this subdivision, “third person” means a person whose right to possession of the property (1) existed at the time of the death of the decedent or came into existence upon the death of the decedent and (2) was not created by testate or intestate succession from the decedent.