Sandra Tennyson

Sandra "Sandy" Tennyson is Carl Tennyson's wife, Ben's mother and Gwen's aunt.

Alien Force
Sandra made a cameo in the first episode, when she was washing dishes and yelling at Ben for running in the house. However, she was a brunette at the time.

In Grounded, Sandra and Carl witnessed Ben and Gwen fighting a Highbreed. She and Carl became angry at Ben for lying to them so many times and forbid Ben from using the Omnitrix. However Ben disobeys them when Kevin is in trouble. Sandra and Carl spot Echo Echo trying to sneak out of the house and then he is grounded. Ben later blatantly disobeys them and transforms right in front of them to leave and help Kevin, and Sandra and Carl realize Ben is trying to protect the Earth, and they realize they were wrong to stop him, they then decide to go help Ben save Kevin. Carl and Sandra save Humungousaur and Kevin from the Highbreed using a Space Bazooka. She and Carl apologized for the mistake they made and promise to never let that happen again.

Ultimate Alien
Sandra returned in Hit 'Em Where They Live, where she along with Ben's family are attacked by Ben's enemies. When she was washing dishes, she was ambushed by Sevenseven without even realizing, but was saved by Max. Later in the episode, she was kidnapped by Zombozo and taken to an abandoned carnival. She was saved by Gwen.

Omniverse
Sandra reappeared in Rules Of Engagement, where Princess Looma meets her.

Ben 10: Alien Force

 * Ben 10 Returns: Part 1 (first appearance)
 * Grounded

Ben 10: Ultimate Alien

 * Hit 'Em Where They Live (first re-appearance)
 * The Ultimate Enemy: Part 2 (flashback)

Ben 10: Omniverse

 * Rules Of Engagement (first re-appearance)

Trivia

 * According to Derrick J. Wyatt,
 * Sandra and Carl approve of Ben's friendship with Rook.
 * In Ben 10 Returns: Part 1, Sandra was a brunette, instead of a blonde, like she was before and after that episode, making it unclear which one is her natural hair color.