Deceased friend

Dave's best friend passed away recently.

Grieving before his grave he said "Mate, I really miss you. My wife has been pregnant for 8 months now. How about you reincarnate as my child?"

A month later, Dave's wife gave birth to a boy.

As his child grew older each day, he realised he looks a lot like his best friend.

Spoiler:

Dave's really happy that his prayer worked.