I am on the board of my co-op and we recently interviewed an applicant. It was for a couple plus one 8 year old child.

I assume that this is for someone that purchased a unit, as opposed to a subtenant. You can move to revoke their master lease, but its not inexpensive or without risk. You are going to need to meet with a a Co-Op attorney.

I agree with my colleague, but I would also like to point out that in making a determination on whether to approve applicants for a unit in your building, it is actually illegal to ask about the number of children they have or plan on having, since this violates the familial status protections of 42 U.S.C. §§ 3601 – 3619 and can be considered an extension of marital status, which is a protected class, as are the categories below: • race • color • religion • creed • national origin • alienage • citizenship • gender • sexual orientation • marital status • age • military status • disability • and, in New York City, both occupation and, • as of March 28, 2008, lawful source of income, which is less a concern with co-ops than with rental landlords discriminating against tenants based on the fact that they receive federal rent-subsidy vouchers or other government assistance to pay their rent. In addition, prospective tenants cannot be informed of the age or number of children living in your co-op by a broker, since it is ALSO a violation of the Fair Housing Act. Your board needs to stop asking this question immediately.

Unfortunately, the Co-op does not have much of a remedy if it was a purchase. (You could send a notice to terminate a sublease to the shareholder if it's a sublet, but even that is difficult.) Let's say they did not lie and simply had another child shortly after moving in. You would be in the same circumstances as now and cannot evict for that purpose. Similarly, once approved and moved in, the Co-op does not have adequate grounds to start an eviction proceeding in the scenario you describe. NYC housing laws are very generous as far as occupancy. The usual rule is there must be at least 80 square feet per person, which is actually very little space. I assume there is no violation of that rule in your case. The bylaws of many co-ops and condos restrict occupancy to no more than two adults per bedroom, which again is not being violated here. So I would counsel against taking any action in this matter.