Sandra Tennyson

Sandra Tennyson is Carl Tennyson's wife and Ben Tennyson's mother. She is first introduced in the first live-action movie, Ben 10: Race Against Time. She wants Ben to call her "Sandra" not "mother", "mommy", or "mom". Her first animated appearance is in the episode Goodbye and Good Riddance.

Alien Force
Sandra made a cameo in the first episode, when she was washing the dishes, and yelling at Ben for running in the house. She reappears in the episode Grounded, where she and her husband witnessed Ben and Gwen fighting a Highbreed officer. She and Carl became angry at Ben for lying to them and forbid Ben from using the Omnitrix. However Ben decides to disobey them when Kevin is in trouble. Sandra and Carl spot Ben 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 leaves and help Kevin, and Sandra and Carl realize Ben is only trying to protect the Earth, and they realize they were wrong to stop him, they then decide to go help Ben save his friend. Carl and Sandra help save Ben and Kevin from the Highbreed using Max's old blaster-rifle.

Ultimate Alien
She and Carl reappeared in the Ultimate Alien episode, Hit 'Em Where They Live, where she along with Ben's family are attacked by Ben's enemies. When she was washing the dishes, she was being ambushed by Sevenseven without realising it, but was saved by her father-in-law, Max Tennyson. Later in the episode, she was kidnapped by Zombozo and taken to an abandoned carnival. She was saved by Gwen.

Original series

 * Ben 10: Race Against Time
 * Goodbye and Good Riddance

Alien Force

 * Ben 10 Returns: Part 1
 * Grounded

Ultimate Alien

 * Hit 'Em Where They Live

Trivia

 * In Ben 10 Returns: Part 1 she 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.
 * Sandra seems to contradict Carl when it comes to disciplining Ben, being more stern than loose, though like Carl, she insisted to be called by her name.
 * Sandra's name is pronounced differently in the movie than the series.
 * She does not appear to be fond of Kevin much; calling him Ben's "ruffian friend". Despite this, she approves of their friendship.
 * In the Ultimate Alien series, Sandra seemed to have a liking for health and fitness, as shown in Hit 'Em Where They Live, where she she was seen exercising in a fitness ball and also rejected Gwen's offer of cotton candy, stating that processed sugar is poison.