When people hear Soft Kitty they probably think of The Big Bang Theory. However, the show merely popularized the rhyme which has existed for decades.

The Big Bang Theory came to an end last year after 12 very successful seasons. The sitcom will be remembered for a number of different reasons. Jim Parsons' portrayal of Sheldon Cooper, the on-again, off-again relationship between Leonard and Penny, and its hand in the popularization of what is now mainstream nerd culture.

Fans of the show will also think of it every time they hear the nursery rhyme Soft Kitty. Penny first sings the tune to Sheldon in season one to make him feel better. It continues to make cameos in the show all the way up until season ten and has even reared its head in spinoff show Young Sheldon. If you've assumed Big Bang Theory's creators came up with the rhyme, you're wrong.

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The rhyme was originally called Warm Kitty and was written and published by Edith Newlin all the way back in 1937, according to ScreenRant. What's more, Warm Kitty was based on a Polish lullaby written during the 19th century. While the original composers of the tune aren't around to be bothered or pleased by its use in mainstream media, the relatives of Newlin most definitely are and were far more bothered than pleased.

So bothered, in fact, that they decided to take legal action against Warner Bros., CBS, and anyone else involved in the creation of Big Bang Theory. Since the song had not only been used in the show but also had various lines of merchandise due to its popularity, Newlin's daughters claimed in 2015 that their mother's work had been used on the show illegally in 2015. When asked why it had taken them this long to react (the show first aired in 2008) Newlin's daughters revealed they had never actually watched the show before.

After two years of battling through the court system, the judge decided to dismiss the case. The ruling was that Newlin's daughters couldn't prove that they still held the rights to the song. Nevertheless, it seems as if Big Bang's creators were rattled. Soft Kitty has only appeared in its shows twice more since then, once in Big Bang and once in Young Sheldon. Perhaps that was their way of saying goodbye to the rhyme to minimize causing any more trouble.

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