Testator left a portion of his estate in trust, with his wife as the life tenant. Upon his wife's death, the trust was to terminate, and the assets were to be distributed to his sister or her heirs at law. Testator's sister predeceased his wife. The sister was survived by her husband, who also died before Testator's wife, leaving the residue of his estate to the Regents of the University of California (D). Testator also had two brothers, both of whom predeceased him. One of the brothers died without issue; the other was survived by a natural daughter and an adopted son. Upon the death of Testator's wife, the trustee bank (P) petitioned for a determination of those persons who were entitled to the trust assets, and whether the sister's heirs at law should be determined as of the date of the sister's death, or the date of death of Testator's wife. The Probate Court found that the heirs should be ascertained as of the date of death of the life tenant, and ordered the trust assets distributed to the issue of Testator's brothers. D appealed.