2 year old suddenly waking early in morning!?

My 2 year old has always been a great sleeper. She goes to bed at 7pm and usually wakes at about 6.30/7am.

The last week she has been waking up at 4.30/5am! I don’t understand why?

Also normally when she wakes she used to just play with her toys in her cot until we woke but now she screams!

She has a 2 hour nap during the day, do I need to stop?

My 6 month old has just started sleeping through the night but now my toddler has started playing up!!

Any suggestions??