In In re Elijah V. (2005) 127 Cal.App.4th 576, 583, the court explained that a biological father may be accorded parental rights and become what is known as a Kelsey S. father when, although he has not satisfied the Family Code section 7611, subdivision (d) conditions to become a presumed father, he has made a full commitment to his parental responsibilities but a third party has thwarted his attempt to achieve presumed parent status under Family Code section 7611, subdivision (d). The factors to consider in determining whether a man is a Kelsey S. father are the man's "conduct before and after the child's birth, including whether he publicly acknowledged paternity, paid pregnancy and birth expenses commensurate with his ability to do so, and promptly took legal action to obtain custody of the child. He must demonstrate a full commitment to his parental responsibilities within a short time after he learned that the biological mother was pregnant with his child. He must also demonstrate a willingness to assume full custody." (Elijah V., at p. 583.) In Adoption of Kelsey S. (1992) 1 Cal.4th 816, an unwed mother made arrangements to have her child adopted at birth by third parties, over the objection of the biological father. Two days after the child was born, the father filed an action to establish his parental relationship and obtain custody. The trial court terminated the father's parental rights, thus freeing the child for adoption. On appeal, our Supreme Court held: "If an unwed father promptly comes forward and demonstrates a full commitment to his parental responsibilities--emotional, financial, and otherwise--his federal constitutional right to due process prohibits the termination of his parental relationship absent a showing of his unfitness as a parent." (1 Cal.4th at p. 849.)