Sleepy KITTY.
The Big Bang Theory Season 2, Episode 21
I sing you "Soft Kitty"
The Big Bang Theory Season 5, Episode 18
♪ Happy KITTY, sleepy KITTY... ♪
The Big Bang Theory Season 5, Episode 6
Sleepy KITTY
The Big Bang Theory Season 2, Episode 21
Happy KITTY
The Big Bang Theory Season 2, Episode 21