Bella was 3 weeks. She isn't smiling tons yet, but I get 4 or 5 a day. You can definitely tell that it's real because their eyes and everything lights up.
lily smiled first at 6 weeks, Linzi, i didnt think Id know either but i definetly did with Lily, her whole face lit up! I read that if u make a massive deal when they do it by accident, they learn it gets the reaction they want!