Mom-Farnsworth relationship

The relationship between Mom and Professor Farnsworth is a recurring theme on Futurama.

Q. T. McWhiskers incident
At around age 90, Farnsworth worked for Mom's Friendly Robot Company, where he designed robots for the company as well as toys, such as Q. T. McWhiskers, but Mom's suggestion of turning the toy into a giant made Farnsworth leave her, because she simply understood him. (2ACV14)

Global Warming situation
Farnsworth later return to Mom's company to work on creating actual robots, but back then, robots were stiff moving and not very efficient. However, when he sacrificed fuel efficiency, he succeeded, unfortunately, this robot design also caused global warming. Why he left Mom this time remains unsettled, but it may be because he once realised she was evil. (4ACV08)

The Wernstrom Affair
At a third account, Farnsworth was once again at the company with Mom, where he discovered the secret of Dark matter, around the time where Mom's sons, Walt and Larry, were born. But when he found out she had left him for Dr. Ogden Wernstrom, he left her once again. It would seem around the time Farnsworth was working for Mom, they got more into their relationship as Mom got pregnant with Igner after Farnsworth left. (Bender's Game)

Mother's Day
On Mother's Day, 3001, during the Robot Uprising, all technology rebelled under command of Mom. Mom's three sons went to get Farnsworth to make Mom happy. But the only way to make Mom happy again is that Farnsworth returns to her, or at leasts fakes doing so in order to reach the remote control she keeps in her bra. The crew and the sons travel to Mom's cabin in the Bronx by means of a cart, meaning that Fry needs to re-invent the wheel. Once there, the Professor does his best to seduce Mom in order to get at the remote control, but then the situation gets out of control and he sleeps with Mom. As the crew grows impatient, especially with robots appearing and trying to kill them all, they flee into the cabin and search for Mom's bra with the remote, eventually locating it hanging on a fan. The fan is reluctant to give it back, as it too is robotic, when Bender and the Comrade Greeting Card crash the scene. Mom asks Bender to return the remote, and after his discussion with the Greeting Card, he manages to return the remote control in time to Mom, who ends the rebellion. Unfortunately, Mom finds out that the whole action was just a plan to get to her remote, and she breaks up with yet Farnsworth again. Even though they're broken up, Farnsworth gets Albino Shouting Gorillas that has bred to scream his love for Mom from the rooftops.