That's a MOCKINGBIRD.
The Big Bang Theory Season 5, Episode 17
A MOCKINGBIRD.
Game of Thrones Season 2, Episode 1
(MOCKINGBIRD whistles)
And you...
The Big Bang Theory Season 5, Episode 17
(MOCKINGBIRD whistling)
The Big Bang Theory Season 5, Episode 17
(MOCKINGBIRD continues singing)
The Big Bang Theory Season 5, Episode 17