What does your wife have against linux? All the porn pop up viruses are on windows, and getting your kid on apple is setting them up to be in credit card debt for the rest of their lives.
Even my senile ass grandparents use Linux and they don’t complain about every little thing like they did with windows. My dad wanted a Mac but free so after hackintosh being too much learning curve for him I used some random Mac inspired configs from the internet for one of the Linux DEs that I’ve never personally used, also no more babysitting and virus induced full wipes.
Parental controls I would do at the router level because eventually kids will surpass you in computer skills. Or maybe they won’t because of seo and ai articles taking over the web.