Heidi Weinerman is Howard's very popular older sister and the host of Norrisville High’s #1 Me-Cast:Heidi@School! She’s tall, beautiful, popular and on the cutting edge of pretty much everything. She is voiced by Cassie Scerbo.
Heidi Weinerman is Howard's older sister and the host of Norrisville High’s Heidi@School, where she updates everyone on what's happening at school. Her show includes a Gossip Report where Howard almost revealed Randy's secret identity as the ninja. She seems unable to remember Randy's name and calls him a name that sounds similar to him, such as "Andy" or "Sandy".
She is on the cutting edge of pretty much everything. She apparently likes attention and publicity since she spends most of her time on her show. She does not get along well with her younger brother, Howard, since she was annoyed when he came to ask her for lunch money in "Gossip Boy" and threatened to embarrass him if he and Randy would ruin the Norrisville High Talent Show in "So U Think U Can Stank". At first she believed that Howard knew the ninja's identity but got angry at him when he supposedly didn't.
Heidi is thought to be tall and beautiful. She has medium length orange hair and blue eyes. Her casual clothes include a beige blouse with a red collar and cuffs. She also wears a red skirt and white stockings with red shoes. She also wears a red hair clip on her right side.
- In "McFists of Fury", it was revealed that she owns a secret piggy bank, which Howard used to buy his McTop.
- She can sing and play the guitar as seen in "30 Seconds to Math".
- She won the Battle of the Bands many times before.
- Her show is sponsored by McFizzles in "Night of the Living McFizzles".
- She was the one responsible for the Norrisville High Talent Show in "So U Think U Can Stank".
- In "McFear Factor", it's revealed that Heidi is afraid of looking like her mother when she grows up.
- "The only dish you know comes with sausage and extra cheese."
- "That was pretty juicy. I'll give you a splart."
- "You know who the Ninja is?!"
- "Howard! I knew you didn't know! Ugh..."
- "If you wonk this up, I will webcast that video of you two taking a bath together."
- "My guitar is missing! Has anyone seen it? It's light pink with dark pink skulls and a strap that says "Heidi Weinerman" in hot pink letters."
- "Howard! Now I'll never win!"
- "Zombies are hot this year. They're everywhere. Literally, everywhere."
- "But you look just like...my mom! (squeals in terror)"