After all the fun with the growth potions, I found there was a potion for altering height permanently. So, I decided to make my ferret taller.
I had to stand next to another of my character's race to show you mammals that I'm now taller in the game. Shame the potion doesn't stack like the growth potion. There is even a potion to change a character's thigh size and my ferret has bigger thighs too now. Okay, I'm a silly dragon.