Penny is generally kindhearted. She is gentle, soft-spoken, and very sweet. She tries to be helpful, but her help sometimes causes unwanted results. She is very sensitive and her feelings can be easily hurt, as shown in Penny For Your Laughs, when Pepper teased her and made hurtful jokes about her (which resulted in Penny bursting into tears). Although, in "The Very Littlest Pet Shop" she simply became irritable when the same thing happened.
Penny's talent lies in gymnastics geared activities, but she is particularly fond of ribbon dancing. She is usually very graceful but can be a bit clumsy, sometimes as a result of others messing her up.
While Penny is sensitive and harmless most of the time, she is also shown to have a temper. In the event that she is angered, she reveals an unstoppable rage. In Mean Isn't Your Color, Penny held a grudge over a clothing design that she believed that Blythe intended for her to wear and scared the other pets with her attitude. She also appears to possess a great deal of physical strength, which is demonstrated on multiple occasions. In Mean Isn't Your Color, she tore a chair apart when she was angry, and nearly crushed Russell and Sunil when she hugged them in Topped With Buttercream. She also hoisted the rest of the pets in the dumbwaiter in The Treasure of Henrietta Thwombly (although she wasn't able to for very long).
Surprisingly, Penny has shown a narcissistic streak and will make comments reguarding her cuteness. She also fantasizes about everyone adoring her in Mean Isn't Your Color. She seems to also enjoy getting compliments on her appearance, as seen in Secret Cupet.
- A spy costume with a black beanie and black turtleneck.
- During Blythe's fashion show, Penny wore a green dress vaguely resembling a kimono. Underneath the main layer was a pale, mint green layer. While lining it was soft yellow material with a single flower in the center, matching the one worn on her small hat.
- An orange version of the above.
- A black hair bow and a necklace.
- A yellow, green, and orange Scottish outfit with brown belt and simple jewelry. Has a light blue paint on one side of her face.
- When imitating Star Trek, Penny is dressed as Mr. Spock. She doesn't retain his trademark emotionless personality though.
- A white top with blue and green colorful skirt and pink half layer-skirt on top. Around her waist was a red cloth, and she wore a black cap with flower on it.
- During The Sweet Shop Song, Penny wore the same glittery dress, white gloves, and blue neck piece as the other girls. She was given a lilac colored wig with single white streak, wearing it up in a curly beehive with a big cherry decoration in it to match her cherry earrings.
- In another she wore a big pair of glasses, a collar piece, and a small bow on her right ear.
- In her fantasy she wore a long, flowing pink dress with white boa and a rose decoration on her right ear.
- Frosting and candy markings consisting of white on the tops of her ears with curly brown designs, purple above her ears, her mouth and below the eyes bright orange, green bead work around her waist, and random dabs of lilac and green frosting.
- In Humanarian she also wears a nurse outfit with orange makeup and a purple puffy 80's style afro wig, a la Shana from Jem and the Holograms.
- A light pink dress with simple lining and a pink beaded crown.
- An Indian outfit with a layer of gold flowers in the middle and gold lining on the outside of it, making the other two sides pink, and a beaded headband with light and dark pink beads in a pattern and a huge gold bead in the middle.
- A barber shop cortet member.
- Dark pink toga-like dress with lighter pink sash.
- A brown, human size tuxedo.
- A clown nose with blue cowboy hat and pink gem tiara.
- A pale pink dress with white designs and a feathery boa. Worn with a pearl necklace, gem tiara, and white gloves.
- A showgirl-like head piece that is gold with dark pink feathery attachements and white markings. Worn with a gold necklace with single dark pink bead.
- A colorful clown costume consisting of a green and yellow top with an orange collar, red pants worn with a blue cloth belt, brown cowboy boots, and a blue cowboy hat. She also has red cheeks, a clown nose, and a bright purple star over her right eye.
- In Bad Hair Day, Penny is shown to have a very big appetite. She managed to eat an entire basket/plate of fruits within a few seconds. In Dumb Dumbwaiter and The Secret Recipe, she finished an entire bowl of popcorn.
- In Frenemies, Penny is shown to be the seventh pet to join the Pet Shop crew.
- She is almost always addressed by her full name.
- Her name sounds like it could have been inspired by the title of the Beatles song, Penny Lane.
- She was the mascot of the toyline, until the Franchise Re-invention.
- Penny's McDonald's toy has her holding a red lolipop, referring to her name in development, "Lolly".
- She also likes to lay on Sunil's belly, as seen in The Expo Factor - Part 2.
- In the episode Sleeper, she seems to have a crush on Mr. Von Fuzzlebutt.
- Penny Ling will meet the FT Squad in The FT Squad Goes to Littlest Pet Shop.
- Penny Ling will meet Team Robot in Emerl's Adventure's of Thomas & Friends: The Adventure Begins
- Penny Ling will meet Thomas, Twilight Sparkle, and their friends in Thomas and Twilight Sparkle's Adventures of Littlest Pet Shop: Blythe's Big Adventure.
- Penny Ling guest stars in Brian Griffin's Adventures of Planes, Thomas and Twilight Sparkle's Adventures of The Terminator, Thomas and Twilight Sparkle's Adventures of The Terminator II: Judgment Day, Thomas and Twilight Sparkle's Adventures of The Terminator III: Rise of the Machines, Thomas and Twilight's Adventure with Jimmy Neutron: Boy Genius