That’s what I thought too the first time I read it, but the second time, I fully understood it now. It’s not that he’s rejected, it’s because the black haired still couldn’t let go of his lifestyle thus, letting the blond go. But after sometime, the mc realized the gang is not forever, they’re meant to grow out of it, and he just needed a push to get out from it. And that’s where the baby came into the scene, he was like “the light of the darkness”, he’s like a sign. The black haired love the blond in his own way, and he was able to let it show openly now that he’s out of the gang, and with the baby. It’s not that he was accepted cause there’s a baby, it’s the baby who has open the door for them to be together. It’s their light of the darkness.
EHO OS THE FATHER AND THE MOTHER!? Also,saying he was born to meet the baby and accepting him then is kinda weird.