Adam Millagan is a supporting character in Supernatural. He is the younger half-brother of Sam and Dean Winchester and the son of John Winchester. He appears as a minor character in season 4 and a supporting character in seasons 5 and 15. He also serves as the primary vessel for the Archangel Michael.

This one is a bit of a doozy, but the answer is yes. Dean accidentally conceived a child with Lydia, an Amazon who had a one-night stand with the Winchester brother in order to have a child. The child, Emma, was born two days after conception and grows up ridiculously fast.