Eric and Donna headcanons, via my EDish parents:
-He was a paperboy as a kid.
-He walks around the house naked, or in his underwear. Donna keeps telling him to stop.
-He thinks "Perfect" by Ed Sheeran perfectly describes his relationship with Donna.
-It's basically canon anyway, but he has a major fear of heights.
-He loves boating, boats, and boat shoes.
-As an older man, he's all about the RV life. Donna can only tolerate him for so long, sometimes.
-As he gets older, he becomes the talker in the relationship.
-He puts way too much butter and cheese on everything.
-If he has a bad experience with a certain food, he will never eat it again.
-He falls asleep watching Aerial America.
-She loves Stephen King novels and Carole King.
-She hates Trump, a burning passion kind of hate.
-She doesn't get along with most of the other PTA moms.
-She has this "not like other girls" vibe as a kid/teen, and even a bit as an adult. Donna mostly grows out of it, but my mom's more introverted, so yeah.
-She buys most of Eric's clothes, if only because he buys too much fandom and ugly stuff. And he buys his underwear too tight.
-She hates when girls squeal and cry when they meet a celebrity.
-She makes really good deviled eggs.
-She takes her kids to the library way too much as a kid.
-She likes the colors of the stuff in the mens' department.
-She buys magazines and books she thinks Eric will like so she can read in peace.