At that age, we had some tummy time, I tried to tempt him with soft toys moving around in front of him, he was trying to roll over, I did so many songs and stories - even Harry Potter! Well, he likes my reading voices. I also had DH tell me off for the biology lectures - well, DS likes hearing different fun words like photosynthesis, xylem, phloem, parenchyma, carotid, jugular, cardic, pigmentation... it's good for their development