^[1]This article originally appeared on Dr. Mahaney’s Pet-Lebrity News ^[2]  column on Pet360.com ^[3] as: The Epic Battle of the Hollywood Cats: Grumpy Cat and Lil Bub Tell All ^[4].

There have been two feline Internet sensations garnering news headlines around the country for the past year, Grumpy Cat and Lil Bub. These famous cats have been busy making their rounds throughout the media circuits and have been entertaining their adoring fans with a scowling glare and a pronounced pink tongue (respectively).

If you’re not familiar with these clever-looking cats, you certainly will be soon as both have released “tell-all” books. The feline stars are trying to outdo each other while clawing to the top of the best-selling charts. Lil Bub’s Lil Book ^[5] and Grumpy Cat: A Grumpy Book ^[6] feature all sorts of flattering photos and tales of their origins and subsequent rise to fame.

We reported back in August that Grumpy Cat, otherwise known as Tarder Sauce, launched her own brand of coffee. Before the coffee venture, Grumpy Cat ^[7] signed on the dotted line to star in her own movie. Now this week, more good news came Grumpy Cat’s way. It was announced that she has officially signed on as the “spokescat” for Friskies. I’m sure Grumpy Cat is “thrilled” in her new role (maybe she even smiled).

“She’s very busy. The first thing she’ll do for us is receive the lifetime achievement award,” Friskies spokeswoman Julie Catron told the Associated Press.

Read More: Grumpy Cat Launches a Brand of Coffee ^[8]

USA Today ^[9] recently profiled these cats and provided the great reveal that both are females along with the following facts:

Grumpy Cat:

Real name: Tardar Sauce

How she got her nickname: Specializes in frowny faces

Age: 1

Other stats: Has feline dwarfism; weighs under 5 pounds

Her human: Tabatha Bundesen

Accolades: 2013 Webby Award for Meme of the Year

Social media: 1 million+ Facebook likes ^[10]; 100,000+ Twitter followers ^[11]

Lil Bub:

Nickname: Bub

Lil Bub’s book is full of Internet-inspired whimsy.

Family background: Born the runt of a feral litter

Age: 2

Why her tongue sticks out: Born with genetic mutations including underdeveloped lower jaw and no teeth

Weighs: 4 pounds

Her human: Mike Bridavsky

Film credits: Stars in Lil Bub & Friendz

Social media: 206+ Facebook likes ^[12]; 22,000+ Twitter followers ^[12]

A documentary about the life of Lil Bub and her owner, Mike Bridavsky, Lil Bub & Friendz ^[13], follows their adventures in life and even includes other “cat-lebrities” like Grumpy Cat. It premiered at the 2013 Tribeca Film Festival and won the Tribeca Online Festival Best Feature Film. Go Lil’Bub!

Interestingly, both Grumpy Cat and Lil Bub have genetic issues related to their breeding, yet both cats are mixed breeds.

Grumpy Cat has a feline dwarfism (see petMD’s Bone Deformity and Feline Dwarfism in Cats ^[14]), a genetic condition having two subtypes:

Osteochondrodysplasia- a growth and developmental abnormality of the bone and cartilage, which results in lack of normal bone growth and bone deformities. Where osteo refers to the bone, chondro refers to the cartilage, and dysplasia is a general term that is applied to abnormal growth. The Scottish fold breed has been found to be predisposed to osteochondrodysplasia of the limbs.

Achondroplasia- is a form of osteochondrodysplasia in which the bones do not grow to the normal size, based on what is expected of the breed. This is caused by a mutation of the fibroblast growth factor receptor gene. The result is abnormally short limbs, a condition called dwarfism. In some breeds this trait is selectively encouraged, such as with the Munchkin breed.

Clinical signs of feline dwarfism include:

-Larger than normal head

-Undershot jaw with shorter nose

-Crooked teeth due to shorter jaw

-Abnormal bone shape

-Poor growth or lack of growth

-Bones appear shorter than normal

-Enlarged joints

-Sideways bowing of forelimbs – front legs are more likely affected

-Spinal deviation to either side of the body

It is presumed that Grumpy Cat’s scowling facial expressions are related to her feline dwarfism.

Lil’ Bub’s unique look with her tongue protruding from her mouth is also related to her genetics, as she has a retrognathic mandible (“underdeveloped lower jaw”) and apparently “lacks teeth” (which could be ectodermal dysplasia or other cause). Her tongue appears fairly normal in size and shape. Therefore, I would not consider her to have macroglossia, a disorder where the tongue is larger than normal.

Hopefully, some of the Internet and YouTube-related fame that is now translating into real-life celebrity will help to bring awareness to the health conditions that contribute to these cats’ unique appearances.

Thank you for reading this article.  Your questions and comments are completely welcome (I’ll respond).

Please feel free to communicate with me through Twitter (@PatrickMahaney ^[15]) and follow my adventures in veterinary medicine by liking Patrick Mahaney: Veterinarian Acupuncture Pain Management for Your Pets ^[16] on Facebook.

Copyright of this article (2013) is owned by Dr Patrick Mahaney, Veterinarian and Certified Veterinary Acupuncturist. Republishing any portion of this article must first be authorized by Dr Patrick Mahaney. Requests for republishing must be approved by Dr Patrick Mahaney and received in written format.