baby name help

Kristi
I'm only 8 weeks and 5 days along so my boyfriend and I don't yet know what we're having but we've discussed names. For a girl I've had the name Rosslyn Cecilia in mind for a long time. It's in honor of two of my grandfathers, Ross and Cecil. For a boy my boyfriend wants to use Dominick Michael in honor of his grandfather and his brother. I fully support his choice but he's not quite as supportive of mine. He likes Cecilia, I think because he's Italian, but not Rosslyn. I told him on two separate occasions about my thought on the girl name and he never said much. When we told his mom that we are expecting he told her that we'd be using her father's name if it was a boy. She asked if we'd talked about girl names and he said no! So I brought it up again and he still didn't say much but his mom loved it. Yesterday my stepsister asked if we'd picked names and I said yes. He said "umm, we've discussed them but they're not set in stone." I said so your grandfather's name isn't set in stone? He said that he's open, but apparently not for Rosslyn. I know it may be a pointless argument because we don't even know yet what we're having but it really upsets me that he's waited until now, after I've had my heart set on this name, to tell me that he doesn't like it. Most women dream of having and naming their own babies from the time they get their first baby doll. Then a man comes along and gives you the baby you've been waiting for and tries to highjack the naming process. I definitely want him to have input on it, it's his baby too. But I don't think that he should ask me not to use a name I've been wanting to use forever, especially since it has such a sentimental meaning and I fully supported his boy name request, no questions asked. I'm afraid it'll turn into a big fight if we find out we are having a girl and I want it to be a happy occasion. Any advice would be much appreciated.