So often, after my baby was born, I would get him out of the bathtub, cover him with lotion, comb his hair, and wrap him up in a snuggly, warm towel. Then I would turn myself and him towards the bathroom mirror and start talking.
"Where's my baby? Who's that boy? Where's mama?"
For several months, I would get a blank stare back, and then a look from mirror to me (and back). Eventually, though, that look back and forth became recognition. And when the recognition started, I loved to play a fun little game to see how much my baby understood.
Just a little dab of lipstick on my baby's nose would tell me if she knew it was him in the mirror or not. When he looked at himself with that red spot, if she knew it was his face and that the spot didn't belong there, he would try to rub her nose and get that spot off! Sometimes, he would even smile or giggle at himself with the funny new thing on his face.
I love, even before he knows who's there in the mirror, seeing him look at that baby in front of him.. A giggle, or swat at the mirror, or even a kiss on his own lips is a funny way that he can connect with the baby and even "make friends" with the boy looking back at him.
When he sees that he and I are there in the mirror, it's so much fun to play peekaboo or make silly faces at him and make him laugh. It became an after-bath ritual for us, and a time for us to bond with each other.