The presumption is that, by the age of 12, a child has sufficient maturity to understand their rights and to make an access request themselves if they wish.
Gwneir rhagdybiaeth y bydd plentyn, erbyn iddo droi'n 12 oed, yn ddigon aeddfed i ddeall ei hawliau a gwneud cais am fynediad at ddata gan y testun ei hun os bydd yn dymuno.