" Maybe you saw this soft-drink commercial. The camera follows a pleasant-looking, college-age young man at a social event in a large house. It’s the holidays, and he is busy introducing you to his various friends and family, singing a song, and passing out soft drinks. There’s his mom, his sis, his brother, his “surprisingly cool stepmother,” and the two kids his stepmom had before meeting his dad, plus aunts, cousins, office mates, his best friend, his judo coach, his allergist, even his Twitter fans. It was the clearest example I have seen that the definition of the American family is changing. Rapidly. It "

― John Medina , Brain Rules for Baby: How to Raise a Smart and Happy Child from Zero to Five