As an older Mum ie, in your MIL age range, I like plants that can be indoor and outdoor. Is it possible to take her out for afternoon tea at the local shopping centre then walk around together just browsing.
She will love the handmade card and maybe your DD can do a drawing for her
This is a great idea, maybe i could make an "IOU" card that says to take her out for lunch, wont be able to take her out on sunday.
With the plants, she LOVES orchards.. we brought her fake (VERY nice ones) and real ones for about 3 years (birthdays, mothers day and christmas) because its all we could think of, then one year she hinted she had no more room for them.. so we gave up on that LOL