Ed. Code, § 24803

(a) If any benefit is payable by a district retirement system to the estate of a deceased person, whether because the estate is the beneficiary of the person or because no beneficiary was designated or because an allowance payable to the person had accrued and remained unpaid at the date of the death, and the estate would not be administered if no amount were due from the system, then the benefit shall be paid directly without procuring letters of administration to the surviving next of kin of the deceased, or the guardians of the survivors’ estates, share and share alike. The payment shall be made in the same order in which the following groups are listed:

(1) Spouse.

(2) Children and issue of deceased children by right of representation.

(3) Father and mother.

(4) Brothers and sisters.

(5) Nieces and nephews.

(b) Payment may also be made to persons in the groups listed in subdivision (a) to the extent those persons are the only beneficiaries under the last will and testament of a deceased former member of a district retirement system, without the probate of the will.