you’ll need to hold them until they’re strong enough to hold up their own heads.
I don’t see that happening. Do you have any idea how much a horse, even a baby one, weighs? It’s not likely a mother centaur is strong enough to carry her baby to breastfeed it.
I think if it was the only way, centauri women would have an evolutionary advancement in the muscles of their upper body. Like kangaroos that are used to carry their kids in a belly pocket. And kangaroos punch like a motherfucker.
It would be funny to see all centauri women be built like MMA fighters and men be thin like a matchstick.
They could always lie down to breastfeed like many animals do. That would make more sense.