Sheldon Cooper's ("The Big Bang Theory" Powers That Be for alleged copyright violations.

It took several years for the family of Edith Newlin to notice that a song used on the CBS show uses lyrics similar to "Warm Kitty," written by the late New Hampshire teacher in the 1930s. Now, Newlin's daughters are suing CBS and company, arguing that, since Edith Newlin was not credited, it leaves viewers with the impression that the lyrics were written by one of the show's writers.

"Soft Kitty" is a lullaby Sheldon likes to hear to feel better. On the show, it goes, "Soft kitty, warm kitty, little ball of fur; happy kitty, sleepy kitty, purr, purr, purr." Here's Sheldon singing it when he's sick, saying it's a song his mother used to sing to him:

TMZ posted a copy of Newlin's "Warm Kitty" sheet music, with the lyrics "Warm kitty, soft kitty, little ball of fur; sleepy kitty, happy kitty, purr, purr, purr." That does seem very close; it's identical, other than transposing "Soft kitty" and "Warm kitty" at the start.

The "Soft Kitty" lyrics have even been used in "Big Bang" merchandise, and the lawsuit notes that the lyrics have been used in their entirety in at least eight episodes since March 2008. The family only discovered what was happening in 2014 when one of the daughters was researching her mother's history for an article and stumbled on a blog post discussing the Soft/Warm Kitty lyrics.

The Associated Press reached out to Warner Bros. Entertainment, but so far there's been no comment. Sometimes these Hollywood lawsuits seem like frivolous money-grabs but in this case -- especially when you read more of the details -- it does seem like it may have merit.

All this fuss over a soft kitty -- hug your "Smelly Cat" tight, NBC, and be thankful this is not your problem!

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