The parent and child relationship between a child and:
(a) The mother may be established by proof of her having given birth to the child or under this act.
(b) The father may be established under this act or, in the absence of a final judgment establishing paternity, by a voluntary acknowledgment of paternity meeting the requirements of K.S.A. 23-2204 , and amendments thereto, unless the voluntary acknowledgment has been revoked pursuant to K.S.A. 23-2209 , and amendments thereto.
(c) An adoptive parent may be established by proof of adoption.