Ummm...you've turned to this forum for an answer like that? LOL. Gotta love the logic of kids...my 5 year old asks some doozies as well!
I did a quick search on google...type in "who created God" (with the quotation marks). You'll get lots of returns....
Here's an excerpt from one....
IN SUMMARY
The universe (including time itself) can be shown to have had a beginning.
It is unreasonable to believe something could begin to exist without a cause.
The universe therefore requires a cause, just as Genesis 1:1 and Romans 1:20 teach.
God, as creator of time, is outside of time. Since therefore He has no beginning in time, He has always existed, so doesn't need a cause.
Good luck explaining that....LOL.