Okla. Stat. tit. 58, § 58-138: Surviving spouse - Assertion of prior right

The surviving husband or wife, when letters of administration

have been granted to a child, father, mother, brother or sister of

the intestate, or any of such relatives when letters have been

granted to any other of them, may assert his prior right, and obtain

letters of administration, and have the letters before granted

revoked in the manner prescribed in the three preceding sections.