My girls are 7 and 4 and are fans of my games (which is nice! :-D) - though they more often watch than play themselves. Some of my games are vey simple (because of my limited coding skills at the time) and / or child-friendly because made them for my kids initially.
Spot the Difference - https://captaind.itch.io/spot-the-difference
Daleks (my daughter did the SFX for this one) - https://captaind.itch.io/daleks
AGS Cycles - they might enjoy playing against each other - 2-player only)- https://captaind.itch.io/ags-cycles
Captain Disaster in: The Dark Side of the Moon - https://captaind.itch.io/captain-disaster-in-the-dark-side-of-the-moon - p&C