Igner

Igner is youngest and dumbest of Mom's sons, he is the only one of Mom's sons to be the son of Hubert Farnsworth. As the dumbest of the three, he is often prone to slapstick events, and unquestionably does what his brothers ask him to.

Igner often makes strange noises in fear of certain events, such as when Farnsworth were to get Mom's remote in her bra. But Igner can actually do the right thing when he puts his mind to it, and while dumb, he is sincere and good at heart. Something which cannot be said by his oldest brother, Walt.

Together with Farnsworth, Igner helped destroy the anti-backwards crystal and effectively the usage of dark matter as fuel. According to Mom, Igner has never been hugged, until Farnsworth requested it.

Trivia

 * Igner was originally thought to be spelled as "Ignar".
 * Igner is the half brother to Walt and Larry, due to his father being Professor Farnsworth.
 * It is revealed that Farnsworth is Igner's father in Bender's Game during a parody of the fight between Luke Skywalker and Darth Vader, in Star Wars Episode V: The Empire Strikes Back, in Momon's cave.
 * Igner's name could be a pun on the insult "ignoramus".

Quotes

 * Igner: Can I wear your fat suit? Mom: No Igner, put that down!
 * [repeated line in Bender's Game] Igner: We're owl exterminators!