I hope your GS wants to learn to knit, I think it's a good thing for people to know how to do. It can be very therapeutic. I remember hearing about football players doing needlepoint or something like that. We're lucky that our SILs don't object, some dads would. So far I've heard nothing about my SIL not liking the idea, I don't think it's likely to be an issue. Anything the little guy likes to do and gets him away from electronic screens is generally encouraged. My DD thinks it's great. We both think that once he's gotten good at it, he'll find it relaxing...unless he gets so hung up on perfection right away that he quits. I really hope that won't be the case. And, yes, it was a good experience for both of us. I'm so glad I finally learned to knit English, that's the way he chose to do it and I can't imagine teaching him to hold the yarn in his left hand. He might learn both ways, who knows?
Happiness is catching that dropped stitch while it's still fixable..