What if tenant lets girlfriend or family members stay for free?

[Mary Joe]

How do most people here handle situations where your tenant starts letting his/her family members live in the property ? or even the girlfriend/boyfriend?

I don't know if this only applies to New York or not, but I heard here in NY if the landlord does not put an end to the situation immediately, then the family members of your tenant will somehow inherit the RIGHT to live in your place even though their names are not on the lease. And even if the tenant dies, his family members can continue to live in your property. That sounds scary !

Is this true? How do landlord prevent these things from happening? Do home inspection regularly and start eviction process if the tenant does not put that to an end immediately??

Thanks
MJ