This is a little girl with delayed development who is learning how to transition from her tummy to sitting up. As you can see, she doesn’t like being on her tummy but she immediately calms once she is sitting up. It would be helpful for her to be independent with this movement so that she doesn’t become as distraught about being in prone (on her tummy). This move starts with her rolling onto her side and then pushing down through the floor to raise her trunk.