Ahadi

Ahadi was the son or son-in-law of Mohatu, the husband of Uru, the father of Mufasa and Scar, the father-in-law of Sarabi, the paternal grandfather of Simba, the great-grandfather of Kopa and the King of the Pride Lands in The Lion King: Six New Adventures book "A Tale of Two Brothers" (which is non-canon to the films and TV shows in The Lion King franchise).

Backstory
Ahadi's backstory is unknown, though what can be said is that he was born to either Mohatu and his wife or unknown lion and lioness some years before the events of "A Tale of Two Brothers". At some point in his adulthood, Ahadi married a lioness named Uru and had two sons with her named Mufasa and Taka.

Ahadi favoured Mufasa and choose him to be his heir, much to the dismay of Taka, who came to resent his father and brother.

"A Tale of Two Brothers"
Ahadi is first seen with his adolescent sons coming to the aid of a mandrill named Rafiki who was about to be attacked by a trio of young hyenas named Shenzi, Banzai and Ed. Ahadi has the hyenas leave Rafiki and sends them away.