She has got a full-size keyboard, she's shown Blair Witch-style footage of her son playing it. He was far more competent than Jack's self-indulgent ivory assault so hopefully his dad is encouraging him to take lessons and he's not under his mother's tutelage.
I must admit I do quite often play my keyboard with only one hand at a time but that's because it is only two octaves so is very smol. Also I'm shit at piano
I stopped lessons twenty years ago to play guitar instead as it's way cooler and easier. Apologies to my piano teacher who would be appalled at Pet Slop Bots even though I am quite sure that my piano teacher is DEAD, EDWINA.