Oh, wow. His business is a solely-owned, passthrough LLC that flows LLC net income through his Sch E. Therefore, when the IRS link says "parent’s sole proprietorship", would his LLC count as a passthrough sole proprietorship?
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If the business is a parent’s sole proprietorship or a partnership in which each partner is a parent of the child:
- Payments for the services of a child are subject to income tax withholding regardless of age.
- Payments for the services of a child under age 18 are not subject to social security and Medicare taxes. If the child is 18 years or older, then payments for the services of a child are subject to social security and Medicare taxes.
