If your child is under 18, it is best if you issue him a form W-2, rather than paying him as "contract labor". Children, under 18, working as employees, in the family business, are exempt from FICA (social security & Medicare tax). So, you enter the business expense as "Wages".
If you pay them as contract workers, they will have to pay social security & Medicare tax, in the form of "self employment tax".
Reference: https://www.kiplinger.com/taxes/hiring-your-kids-tax-benefits-and-rules
