Wired computer mice might seem archaic, but they're incredibly easy to use. If you're looking for a mouse for your child, this one could work very well.
From OnBuy
Xtrfy M42 Wired Optical Ultra-Light Gaming Mouse Usb 400-16000 Dpi Omron Sw M42-RGB-RETRO
Ecprof
M42RGBPINK - M42 Wired Optical Ultra-Light Gaming Mouse USB 400-16000
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