I appreciate the sentiment but couldn't resist being a smartass and got scolded for mansplaining by the facebook friend who posted this. Looking at the figure on the right you observe a large amount of bone between the bottom of the roots of the teeth and the margin of the mandible, this is a very masculine jaw, the foreheads also, on the left quite delicate. You can be very confident we have a boy and a girl. The wisdom teeth on the boy are well developed and not crowded but not yet fully erupted, typical for an 18 to 20 year old. I've only had first year anatomy but looking at the girl the second molar is tilted and I don't see the wisdom teeth at all but she would have a problem fitting them, with less confidence I think she may be younger.