Cow and Chicken

Weasel wears one of those "I'm With Stupid" shirts for the whole I Am Weasel segment.

The Red Guy's Roles on C&C: Fly exterminator, Gorilla Scout counselor.
The Red Guy's Roles on IMW: Mr. Rumpstein Attorney at Law, Warden.

After cousin Sow is sent away to reform school she is never seen or mentioned again.

The Red Guy's Role on C&C: Principle Red
The Red Guy's Roles on IMW: Flight Attendant, Nurse

In "Sow and Chicken", The Red Guy says CornCob Man is his favorite super hero, yet back in "Who is Super Cow?", he was disgusted at the name CornCob Man, and his uniform.

If you look at the board behind the teacher when Cow takes her dog to school, it says "shut yer tarps".

Me an' My Dog is the first episode to show a time card.

It is revealed in the episode Me an' My Dog that Cow weighs 460 pounds.

The Red Guy's Role: Pet Shop Owner

How could Kevin have a litter of puppies, if he's a boy?

Dad's trousers fall down repeatedly in the episode "Chicken in the Bathroom" revealing his underpants to be white with red hearts on them.

Cow and Chicken's grandma makes her first appearance in this episode since the pilot "no smoking".

The Red Guy's Roles on C&C: Grandpa Salesman, News Anchorman
The Red Guy's Roles on IMW: First Mate Red, Babysitter

Greta, the P.E. teacher was also the school nurse in "Sumo Cow" although in this segment, Greta has red hair.

The Red Guy's Roles on C&C: Bunny the Stewardess, Himself
The Red Guy's Role on IMW: Vampire Hunter

The Red Guy's Roles on C&C: Dr. Lackslacks, Dr. Hineybottom
The Red Guy's Role on IMW: I.R.'s "wife"

We learn that Weasel is a family man: with a hispanic wife named Conchita, and two weasel/human kids. The Red Guy pretends to be Baboon's wife.

When Baboon gives Weasel a weenie on a stick, Weasel says the weenie is upside down. How can you tell?

Red Guy's Role on C&C: Dr. Hiney Bottoms, Boss

Cow makes a cameo on the bus in I am Weasel.