This is our 3rd and have never heard of the skull theory before. That being said, 15 week scan, little one likes having crossed legs. But both my others had similar skull shapes and we have a girl and a boy. Here is #3’s ultrasound.
Wasn’t really looking for guesses. Just was curious how accurate people really think they are. Science shows boy vs girl skull shape differences, most the models tend to be of adult structures. As I said, my daughter and son had very similar structures, so was curious how it could be accurate since each child is different.