Well, each woman probably has their own style and/or attitudes about gifts.
Do they equate dollar "amount" to "quality" of the gift?
How about a family portrait? For each of them? With them in it?
Or, get a gift certificate for a nail pedicure or "spa" type massage?
One time, I got my Mom a gift card from our local car wash.... and she LOVED it! Since she is "old" and gets too tired to do it herself. So, throughout the year, she was able to get her car washed/polished whenever she wanted, and it was a real treat for her.
Or, another one which my Mom liked, is we got her a "maid service" to clean all the windows in the house. I usually do it... but, this way, it was helpful for my Mom, and me... and she really appreciated it.
At this age, they can't or are not able to do the house "maintenance" type of heavy cleaning... so any help they have, helps them. At least for my Mom, she likes this sort of thing.
Good luck,
Susan