Search Results: cousin thinks i like her husband

So, I had a conversation with my cousin a few days ago. I told him that, should I be blessed with kids, I want my husband and I to combine our names to make one new name for our kids, for example: Robinsonweller or Robinsmith/Smithrobin.
He thinks I'm being selfish because my husband of would not be able to stake claim as them being his kids; I will still have my name as their last name. I think it should both our names became we are both their parents. So, should we have a child, a girl, it would be: Theodosia Adrienne Marie Robinsmith/SmithRobin.
I think that is cute because it gives the child the best of both worlds.
I donno, I'm probably being stupid.

So my mother has been dating a man, we'll call him T, for about 5 years. My mother and T plan to get married. T has a nephew (his brother's son.) My mother is absolutely convinced the nephew and I are "a match made in heaven" so she has been trying to set us up. The nephew and I have gone on a few dates and we do get along quite well.
So what I want to know is whether or not it is okay to date (possibly marry since I don't date without that in mind) someone my mother's husband is kin to.
I'm not sure if there is such a thing as step-cousin.
(I also do not think of the nephew as a cousin since he and I only met after I was already full grown and I do not consider T a father figure since I actually grew up with my dad.)