jackhelmet
A person so brainless they think a jackass is a kind of pet and a jimmyhat is a hat that talks back.
My mom is a jackhelmet. She tried to knit a sweater and ended up with a hat that looked like a potato.
My teacher is a jackhelmet. She gave us a test and then forgot what the questions were.
My dog is a jackhelmet. He tried to bark at the TV and got yelled at by the remote control.