It's so amazing how a child is able to manifest habits and mannerisms of people around him, particularly parents.
I've noticed my son's habit of playing with his waving both his feet before going to sleep or upon waking up. I really can't attribute this to genetics or I'm just underestimating my son's ability of observing us, thus imitating what we do be it consciously or unconsciously.
The waving of feet is one of my husband's mannerism, particularly upon waking up. I've noticed my son, more than twice already, doing the same thing with his feet whenever he drinks his milk before going to sleep.
...an observation which I find amazing!