Do you think the exact second a couple conceive a child makes any difference to what that child eventually physically and personality-wise turns out like?

Or is there actually a pre-conceived order that means a couple's first born child will look a certain way, their second child a certain way, regardless of when they actually have sex? In other words, there's almost a pre-programmed list of children, so that say, your fourth child is destined to look and act a certain way years before you actually ever have it, if you do indeed ever have it.

I just think it's weird that if, say, a 1 minute difference in your parents getting down might mean you look or act a completely different way than you eventually did.

Does this make any sense at all?