My baby has this thing with his leg. It's random, but it will shake like when you scratch a dog's butt and their leg shakes. I asked doc about it and she said to video it but like I said it's very random. It doesn't hurt him or anything and he's very strong for his age, no problems with his leg strength. Also, i remember while pregnant with him i would feel a big flutter and ob had said it was normal. He has his two month app coming up soon. Has anyone else's baby had this if so what was it? I deff plan on making her look more into it.