Toddler sleeping apnea?

Savannah

My stepdaughter is 4 and is literally constantly tossing and turning. I always check on the kids ALOT during the night and she is always doing it. I just sat in the room for like 5 minutes to see if she would stop and she literally did not stop tossing. I woke her up to see if she maybe needed to pee but she said no and went back to sleep. But I've noticed this everytime she sleeps. She also sweats alot during her sleep and randomly sits up. But she's been acting out alot more lately and I'm wondering if it has something to do with it or just her age. Any body's toddlers do this at night and did y'all ever find a reason why?