SIL and baby name

i would explain, can i ask tho are YOU pregnant? as you dont say?

if not and she has a boy and uses the name it may be tricky! so i would explain to her about the importance of the name to you, she may then decide not to use it, but she may still use it, keep your fingers crossed for a girl!

have to say we had names we really liked and when the babies were born we chose names that were not even on our list a few times, so just because she is set on it now does not mean she will use it.

I would just explain - 7 generations is a lot and a shame to stop. I can't see why it stops it being a second name.

I would first talk to SIL about using the name as well, see how she reacts, but making clear that you would take her opinion in consideration, not necessarily follow it.
If she has a girl, I believe you obviously can use the name: first come, first serve.
If she has a boy, I still think you can use the name as a mn (after all they are mainly here to honor family members), if she does not want you to use it as a first name and you accept it.

Last, maybe you could find a solution with different nn? You could both have the same name for your sons then. E.g.: two Edwards, nn Eddie for one, Ned for the other would be alright with me.

I would certainly use it if they have a girl. If they have a boy, perhaps use it for your DS too but as a middle name?

I am in a very similar position: DBIL & wife named their DD a name which has been in my family a long time - my middle name too.

Now that we are expecting, if it is a girl we will use this name as middle name - no one minds. Quite nice for the cousins to share a name in a way I think.

I would tell her that you will want to use it if you have a boy because it's a family name, explain the history on your side.

Also, remember they might not be telling you their 'final' name - I thought we had a final name for DS, and then we went for dinner and suddenly DH mentioned the name we have gone with, and it just seemed right.

I'm surprised your DH says no even if your SIL has a boy, could it be that he doesn't really like the name and would only go along with it because of your family tradition? This gives him a good 'out' without having to say he doesn't like it. Could you probe a little on that, you might have to rethink yourself.

Just explain. And things may change anyway - I was 'decided' on my daughter's name for years... Until about month seven of being pregnant.

I would explain to SIL exactly what you've said here - that it's a family name on your side and that you will use it if you have a son. If she still wants to use it, fine.

I would just use the name regardless.