The main problem being that it's actually his own voice and not one he's created, which makes life as a parent challenging.
Currently starring in 'Murder on the Orient Express', Gad has been doing the promo rounds with appearances everywhere and wherever he goes, the Olaf questions follow him around because A: 'Frozen' is the thing he's best known for and B: all anyone hears when he speaks is Olaf the snowman.
Unfortunately for Gad, his young daughters don't appreciate their father's 'Frozen' voiceover acting abilities as much as they should.