The Meta Quest store has comfort ratings for all games, indicating the likelihood of motion sickness. Children are particularly prone to motion sickness in VR,

The Meta Quest store has comfort ratings for all games, indicating the likelihood of motion sickness. Children are particularly prone to motion sickness in VR, partly because their proprioception is less developed and also because they often have narrower IPDs than the headset minimum. There are a variety of tricks that help a great deal when using joystick-based movement controls; while they don't work for everyone, they can work for a good majority of users when implemented well. There's the obvious stuff like being absolutely fanatical about controlling motion-to-photon latency and avoiding violent and uncontrolled camera movement, but there are a variety of less-obvious stuff like using vignetting to reduce the FoV during motion and making all acceleration instantaneous. I'm occasionally prone to motion sickness when playing some flat-screen games, but I've had no issues with games like Onward and Ancient Dungeon on the Quest.