Mother's Day question

I'm a FTM due in July, and my son will be her first Grandchild.  She is BEYOND excited.  I'm wondering if it's appropriate to get her a 'grandma' gift for Mother's Day (I'm thinking a bracelet, she loves Alex and Ani and Pandora...), even though little one won't be here for a couple months?  I know she would love it, but not sure if I should start with that stuff now or wait until after because there will be plenty of other opportunities... thoughts?