"Flush!" is one of the Oobi shorts.
Uma thinks the sound of a toilet flushing is hilarious. In the bathroom, she flushes the toilet again and again. Grampu laughs along at first, but he soon gets annoyed and tells Uma that he's had enough of the noise. Uma decides to imitate the toilet flushing by moving her thumb up and down. She later convinces Grampu to join her, and they do a "flushing" dance together.