Well, I have to admit that it's been a while since I've had a baby reindeer. But if I remember correctly, it usually happens in the late fall or early winter. The reindeer mother gives birth to one or two calves, and they're born with soft, fluffy fur that helps them stay warm in the cold weather. They're also born with a unique set of antlers, which are much smaller than their parents' but will grow to full size as they get older.