I Hate People Who Make Fun Of Disabled Kids

i am stuck in a wheelchair due to me being paralyzed from my waist down.
but the last time i went shopping with my mum 2 teenagers were pointing at me a i went past. one asked "what do you think is wrong with her?" and the other said "either the mum is lazy or shes just a retard" and the walked off laughing before my mum could say anything.
i can take insults and not let it show but it hurts.