T.S.
Yvette,
That's such a hard choice. I'm sure some responses will say "it doesn't matter what you spend, it's the thought". I agree 100%, but at the same time I'm one that just likes to be fair. For example, my brother is getting married next month and I've called my sister everytime to see what she was spending on each shower gift and the wedding gift. I'm in no way in competition with my sister, but I don't want to look cheap OR make my sister look cheap. We've always done it this way.
If I were you, I'd do one of 2 things...
First of all, $50 spent on a 1 year old can go a looooong way in their world of toys. Maybe you can talk to her and suggest that she spend a total of $50 or $75 between your two kids at this point. As they get older, it will be more of an issue as the gifts seem to get more costly.
The second option is to spend the $100 like she is. At least that's what I would do.
We have a group of friends that gathers monthly so the kids can play and we can visit (we all went to high school or college together). Although similar, we are all in different financial positions. We used to do a grab bag, but one persons idea of a good amount was different from someone elses. At this point, we've decided that we all buy for our own kids and bring it for them to open. That way, we spend what we want on our own child. We say the present is from "Santa".
T.