I guess this is more of a general tax question.

I have a client whose only income is on a partnership K-1. The partnership did not pay the partners through payroll. It's a family partnership: mom, dad, and son, and they all live in the same house, which is also where the business is. The partnership pays all the home expenses (and yes, I know not all of those expenses are deductible, that's a totally different question for the partnership return) so the son doesn't really have any expenses. So he doesn't need an "income" per se. He just works at the family business, which pays all his bills. Mom and dad have retirement income and social security. 

The son is the client I'm asking about. The partnership absolutely did not pay him, even giving him any draws. But he does get to claim 50% of the partnership profit as active, qualified income. However, when I select that as active, qualified business, it doesn't seem to kick in the EIC. Am I doing something wrong, or is partnership income not considered "earned income" for the purpose of EIC?

I've read several different sources of IRS instructions on EIC and I don't see anything that says anything about partnership income except salary received from a partnership. Nothing about K-1 income. Does anyone know if my hunch is correct, and that the son would not be eligible for EIC?