[SaveTheChief]

What if a baby is born premature? Does it not become a human or feel pain until it serves its full time (9 1/2 months)?

That is an excellent point.

[Orbiter]

So an "unalive" human kicks because:

1. Frogs need to jump soon after hatching.

2. Nerve endings, ligaments, and muscles are practicing for the day they'll "evolve" into self-sustaining organisms.

3. For similar reasons "alive" humans yawn.