Neb. Rev. Stat. § 71-640: Neb. Rev. Stat. § 71-640

(1) Until the registrant's first birthday, given names may be changed upon written request of (a) both parents, (b) the mother in the case of a child born out of wedlock or the death or incapacity of the father, (c) the father in the case of the death or incapacity of the mother, or (d) the guardian or agency having legal custody of the registrant in the case of the death or incapacity of both parents.

(2) At any time after the registrant's first birthday and until the seventh birthday, given names may be changed upon written request as specified in subsection (1) of this section and submission of one or more items of documentary evidence to support the change.

(3) These procedures may be employed to change a given name only once. Thereafter, and at any time after the seventh birthday, given names may be changed only upon submission of a court order.