At age 35, otherwise healthy and having spent 10 years in Herman Miller Aeron chairs, I had hip problems and a small but growing waistline. Then I transitioned to working from home and built my own standing desk (sadly before the very affordable mechanical Ikea standing desk was first released... But which I have now happily used for years). The first few weeks were challenging, but within three months I could stand…
Like anything, sitting, standing, jumping - it's worth doing everything within reason. Possibly just switching between positions throughout the day.
Of course, these things can be gene dependant as well, but if you already have some spider veins showing, hopefully you can be a bit more aware of the problems that can come about later.
She really suffers badly from all those years and it's not something that's easy to fix.