Homestar Runner "Those Darn Cousins" (Unfinished 2000/2001 Flash Animation)
Homestar Runner is a Flash animated web cartoon that began in 1999 and, while its popularity has waned, is still known about to this day. However, some "toons" on the website were left unreleased/unfinished. Among the unfinished ones is "Those Darn Cousins", which was made around 2000.
The plot involves Preshy and Rafferdy (voiced by Emily and Colin Chapman, niece and nephew to the Chapmans), Homestar's cousins, visiting him. They act like angels around other people but torture Homestar when no one is looking.
Parts of the short can be found on the "Everything Else, Volume 2" DVD as part of "Why Come Only One Girl?".