What's a Squishy?

Last week Jarren and I were reading a book; and in the book 2 boys gave somebody a squishy. They put 2 ketchup packets underneath the toilet seat, and then when somebody sat on it the ketchup squirted all over. At the time Jarren thought this was great. But then I made the mistake of thinking that he had forgotten about it. Well...Jarren decided to try it last night without anybody knowing about it. Sweet little Maya was the unsuspecting victim. I ran up the stairs to the bathroom to hear Maya saying, "There's ketchup on my underwear and in the toilet." We'll see if Jarren gets to read those book again.