- "Come with me..."
- ―Albert Green
Albert Green is a one-time only character appearing in Sibling Rivalries. He is the principal of Wisconsin Elementary School in 2013, appearing only in Locker 239. Patrick McReary gets in trouble three times, and Green drags him away to his office.
After Season 1, Green has not appeared again in the series. It is unknown what happened to the character, although he may have quit working at the school. Since Season 4, his step-son Mark Leone has taken over as the school's new principal.
- After "Locker 239" was written, the author saw that Albert Green may have been too strict, which is why he had replaced him with a nicer principal named Mark Leone (who was later said to be his step-son).
- Albert Green was similar to Mr. Howard from the Nickelodeon sitcom iCarly.
- Albert Green and Steve Madison were the only characters of the series that did not reappear in the special "Like Father, Like Sons (And Daughter)".
- Sibling Rivalries Pre-Series
- Sibling Rivalries Main Series
- Locker 239 (one-time only appearence)