Inspiration and ideas for a risk-adverse woman turning 70?

Hi! My mom is approaching a major milestone birthday and I've been looking for a meaningful book for her. She is a voracious and curious reader. She lives alone, used to have a lot of hobbies, but remains very outdoorsy. Over the past few years, however, she's become increasingly homebound. Not for lack of physical or mental health, but more so because it's her safe and familiar place. I wouldn't call her scared or paranoid, but these days she is extremely risk-adverse, calculated, and avoids nearly everything outside of her comfort zone, a zone which has narrowed considerably over time. She loves spending time with her grandkids, and I watch her being less timid when she's with our family. But when she's by herself she just sits still, reads, and reflects. I don't expect her to skydive or become a monster truck driver, but I want her to feel more emboldened to stretch her wings back out a bit and discover new ways to enjoy life – even if that means just eating a piece of sushi (which she loved for a long time and never had any issues, but now doesn't want to risk making her sick). I appreciate any recommendations! And in my words I don't mean to belittle her or presume she's unhappy. I just want to help encourage her that's it's okay to live just a teensy bit "more." Our family loves her to pieces!