It's mean to put soap on your brother's toothbrush.
Mary and her brother like to joke around with each other.
Mary wants to play a prank on her brother.
Mary decides to put food coloring in her brother's toothpaste.
Mary puts dish soap on her brother's toothbrush.
Mary and her brother have a good laugh, and no one is harmed in the end.
Mary's brother gets sick after brushing his teeth with dish soap.