The mum game of all mum games in my experience is The Sims. I've got mine hooked on Sims 2 by accident and it's actually fairly innocent if your playing style is.
Even though any simmer will unavoidably become a genocidal maniac, at some point. But for sensitive people, this might still be a good game.
However, if that's too dark still (because even Sims 4, the most innocent entry, can have inter-character drama), maybe some farming games may work. The kind you'd find on Facebook. Mine is playing those a lot, but I can only think of Farmerama, right now. But that can also be a money milking machine.