daddy everything

MaMa was Tyler's first word. He's been saying Mommy for quite some time. So why now has he started calling me Daddy? If I point to a picture of our family and ask him to point to Mommy, he points right at me. Then turns around not much later and giggles with his arms out for me and says "Daddy!" I think he's a joker and gets secret enjoyment out of teasing me. It is crazy scary how similar his personality is to mine.