That's lovely Joe. I bet they look on you as an absolute gem.

My father was like you, very handy and clever with 'fixing things'. He had his own father's tools and equipment (really old, beautiful tools, sets of chisels, planes, brace-and-bit etc) and he always encouraged me to spend lots of time in his big shed watching and helping. I learned all sorts from him.
I think your best bet is to let your daughter-in-law watch at first, and help in small ways. She'll learn more easily that way. Then maybe give her a small project to tackle while you keep an eye on her. She'll soon gain confidence, as she seems to have an 'inclination' for DIY.

By the time I was about twelve, I spent loads of time in that shed on my own, making all sorts of stuff and using all the tools correctly. I bless my father now, as I'd say I'm quite a handywoman!