My 2 yr old keeps wriggling out of his blanket in cot as soon as he is laid dwn to sleep.... He is in a little sleepin bag but manages to sit himself up and cant get bk up if he falls bk in the cot etc, he still wobbly wen sittin, has hypotonia, severe epilepsy etc... any ideas? Driving me NUTS, wen he wakes up in the night, which can be a LOT....all he wants to do is sit up , even tho cot quilt tight around him, nightmare