The way his brother is drawn?
I have a friend with whom I was in Kindergarten through 11th grade; he had to do senior year THREE TIMES, and now he is built like a tub of lard.
BUT.
In high school, he was literally built like this guy; 188cm, 115Kg, and built like a brick shithouse. (That's 6'1" and 250lbs, in Freedom Units)
Also, I took her mom's height to be a function of the protection of her name; once you can Say Her Name, and obviate the protective spell, she is no longer an imposing height, but just... herself.