She is holding the weight with her left hand - but her right hand thumb is hyper-extending when she holds the slide. 3 fingers, bottom of the slide brace. That thumb is just bending back so far. Even if I have her bend her thumb in the opposite direction (making more of an "O" shape than a puppet face shape, if that makes sense), her thumb still just pops back. She isn't squeezing hard. It's weird.