Agreeing with hS; I reckon a centaur baby would have to be born more or less like a foal, ideally in "diving position" with hooves and head first. In the centaur's case, though, you've got a whole torso coming between the front legs, and may or may not need the arms to also be in "diving position" depending on how developed the humanoid shoulders are. That might be one of those things you don't want to let your audience think about too hard, or they might remember how impossible centaurs are. {= )

Horses can also deliver foals in breach position (hind end first), but as in humans, this is more dangerous and may not be successful without assistance. Twins are extremely dangerous in horses, partly because one twin is often breach, partly because they may both try to be born at once and get stuck, partly because labor takes longer and one or both may suffocate in the womb if the placenta detaches too soon or the umbilicus is compressed or torn.

If you want to check out some foalings for reference, the channel Friesian Horses has several videos showing the entire process. It's not for the faint of stomach, but absolutely fascinating and, IMO, beautiful.

~Neshomeh

1: Good flippin' question. I had to do the reverse of this with Agent hS, and managed it (I hope!) by pushing him more towards listening to others rather than suggesting his own ideas. For Éowine, you could have him show a tendency to believe his own plan is always the best one - but also make him right. That puts him on the border between 'not listening to anyone' and 'actually better at this', which leaves the reader room to wonder. Obviously that doesn't mean he should always get his own way - but sometimes, when he doesn't, things go a bit wrong. Obviously he's too superior to actually comment on this... ^_~

2: Don't know about the differences, but I assume centaur childbirth would be closer to horse than human. Humans are born useless because their heads are the biggest part of them, and have to meet the constraints of the pelvis; a horse body can have a wider pelvis (walking upright has not been good for our reproductive biology), but also I think the body is larger relative to the head, so a centaur can be born precocious (ie, able to walk from birth).

A quick check shows that a key difference is that a foal's feet come out first, and appear some 20 minutes before full delivery. Humans are usually (and most safely) born head-first, and come out very quickly: once the head is out, the baby follows at once. It looks like horses don't have the hours of contractions beforehand, though, so that's a point for their side - and yeah, I reckon a centaur would be horse-like in this respect.

hS