Cal. Probate Code § 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: (1) If the homestead is set apart for the use of the surviving spouse or for the use of the surviving spouse and minor children, out of community property or quasi-community property. (2) If the homestead is set apart for the use of the surviving spouse or for the use of the minor children or for the use of the surviving spouse and minor children, out of property owned in common by the decedent and the persons entitled to have the homestead set apart, or out of the separate property of the decedent or, if the decedent was not married at the time of death, out of property owned by the decedent. (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.