Grumpy Cat, also known as Tardar Sauce, was born April 4, 2012. She first came to fame on Sept. 22, 2012, after Bryan Bundesen, the brother of her owner Tabatha Bundesen, posted a photograph of her on Reddit. The photo went on to rack up more than 1 million views on Imgur in 48 hours. Grumpy’s permanently scowling expression, caused by her underbite and feline dwarfism, made her a viral sensation — especially after her family posted a few videos of her on YouTube in response to Redditors’ accusations that the image was Photoshopped. Grumpy’s frown quickly captured the mood and imagination of a disgruntled nation, and at the end of the year, MSNBC named her 2012's most influential cat.