The song is originally based on a Polish lullaby, "
Wlazł kotek na płotek" ("The kitten climbed the fence"). The lyrics were noted by folklorist
Oskar Kolberg in 1837, and the tune was first published by
Stanisław Moniuszko in 1849, based on a Polish folksong.
Władysław Syrokomla and
Wiktor Każyński published a version of this song in 1857, in
Pieśniach ludu polskiego ("Songs of the Polish people"). The 1972
Tom Glazer album ''Music For 1's & 2's'' features the song under the title "Nice" Versions of the song have been released by Australian children's performer
Patsy Biscoe, and by the long-running
ABC children's program
Play School—a recording sung by Philip Quast and Barbara Frawley was released on the show's 1993 album
The Best of Play School, which predates
The Big Bang Theory and has the lyrics reversed, instead going: "Warm kitty, soft kitty, little ball of fur. Sleepy kitty, happy kitty, purr purr purr." The song remains part of
Play Schools catalog of children's songs regularly performed on the program: the show's presenters occasionally perform the song for their young viewers. ==Copyright lawsuit==