Onions contain a compound which is toxic to the red blood cells of cats. The red blood cells are destroyed and this results in anemia. The specific type of anemia is called 'Heinz body anemia' because the red cells develop an abnormality called a 'Heinz body' which can be seen under the microscope.
Dug, the dog, is easily distracted by ... squirrels (well, he's easily distracted by everything, but especially squirrels). He can be talking (yeah, it's Pixar/Disney so the dog talks) & right in the middle of the sentence, he shouts, Squirrel!. Then he carries on with whatever he's talking about.
Gumby's principal sidekick is Pokey, a talking orange pony. His nemeses are the Blockheads, a pair of humanoid, red-colored figures with cube-shaped heads, who wreak mischief and havoc. The Blockheads were inspired by The Katzenjammer Kids, who were always getting into scrapes and causing discomfort to others.