First read:

Family Help | Internal Revenue Service (irs.gov)

Why It's Tax Smart to Hire Your Children | Nolo

My main question is where do I enter it in TurboTax? It seams like if I enter it under "Employee wages and work credit" I have to issue a W-3 form. Thank you

why wouldn't you? if you hired a family member, they are to be issued a W-2 and report that income on THEIR income tax forms. 

I agree if the family member is an adult, but in this case is a child. If I issue a W-2 to a 12 year old, it means they would have to file a tax return. Issuing 1099- MISC/NEC  would make it as self employed income - again, would have to file a return. 

why do you believe there be an exception for a child?

they worked like an adult, they were paid like an adult, taxes are due just like an adult, etc. etc. etc.