I honestly thought that reveal was going to be way more complicated than it was. The major twist in 'The Alpha's Unknown Heir' hinges on the identity of the child's mother, Lyra. For most of the book, the pack believes this human surrogate was just a random woman who died in childbirth, a convenient plot device. The moment the Alpha, Kael, finally senses a faint, familiar scent on the child's blanket is the turning point.
It wasn't a stranger. The heir's mother was Kael's own supposedly deceased fated mate, Selene, who he was told died in a rogue attack years ago. She didn't die; she was hidden by a rival pack, her memory magically suppressed, and used as a breeder in their scheme to weaken his bloodline. So the 'unknown heir' isn't just some random kid, he's the son of the true Luna, and his existence proves a years-long conspiracy within their own ranks. The real gut-punch is that Kael spent years mourning her while she was alive and enslaved, forced to bear his child without knowing him. Makes the final confrontation less about claiming an heir and more about rescuing a stolen family.