453.015.  Definitions. — As used in sections 453.010 to 453.400, the following terms mean:

  (1)  "Minor" or "child", any person who has not attained the age of eighteen years or any person in the custody of the children's division who has not attained the age of twenty-one;

  (2)  "Parent", a birth parent or parents of a child, including the putative father of the child, as well as the husband of a birth mother at the time the child was conceived, or a parent or parents of a child by adoption.  The putative father shall have no legal relationship unless he has acknowledged the child as his own by affirmatively asserting his paternity;

  (3)  "Post adoption contact agreement", a voluntary written agreement executed by one or both of a child's birth parents and each adoptive parent describing future contact between the parties to the agreement and the child; provided, that such agreement shall be approved by the court under subsection 4 of section 453.080;

  (4)  "Putative father", the alleged or presumed father of a child including a person who has filed a notice of intent to claim paternity with the putative father registry established in section 192.016 and a person who has filed a voluntary acknowledgment of paternity pursuant to section 193.087;

  (5)  "Stepparent", the spouse of a biological or adoptive parent.  The term does not include the state if the child is a ward of the state.  The term does not include a person whose parental rights have been terminated.