Consider making a great quilt that can be raffled for her favorite charity. If she was a dog lover , donate a quilt to a rescue group, or local shelter... you get the idea. I tend to favor charites for this type of project that reflected the life/loves/things that brought joy to the life of the donor ...
I favor local charites that often have not publicized their needs or get the big publicity like many organizations.
It will come to you the right project for the right organization .. you will feel her heart leading you.