In that case I would go with what heather said too.

But it makes me wonder, surely if your GF did not like his name then your Nana would have known this and yet she was so happy for you to want to use it.
Yeah, I know! I couldn't believe it when I found out he didn't like his name and nan had said nothing! If we had done it when he was alive though, he wouldn't have said anything either! They were very "whatever makes you happy" genuine people. Which is why I've struggled with this one because I know if they were still here and I asked them, that's what they'd say

Sarah - the alternate is a good idea too, might see what we can come up with.

Thanks for all the ideas everyone. You know what'll happen though. When the time comes for #2, we'll agonize over this and we'll have another girl