This is true no matter how young a child or young person is, although the weight their opinion is given should change as they grow up and become more mature.
Mae hyn yn wir ni waeth pa mor ifanc y mae plentyn neu berson ifanc, er y dylai'r pwysau a roddir i'w barn newid wrth iddynt dyfu i fyny a dod yn fwy aeddfed.