Who was the father of Mom's children? We know the answer to one of these, but have the others been given a father in canon?
Walt and Larry were probably fathered by Wurnsturm, who is Mom's on again off again ex-husband. Walt probably has Mom's characteristics (black hair, heart shaped face) while Larry looks like his father (brown hair, slender face). SPOILER ALERT: DO NOT READ FURTHER IF YOU HAVE NOT WATCHED 'BENDER'S GAME'. Ignor's father was revealed to be the professor in 'Bender's Game'. His head is shaped like the professor's head, although I still can not explain the purple hair. Must be a recessive gene.
mom dumped the professor for her ex husband worndstrom which would presumably be shortly after Igner would have been conceived. But the professor and mom seemed to have been "shacking" for quite some time so I would imagine that her and Worndstrom were still seeing each other
The professor. He was hooking up with Mom back in the day.