(BOTH CHUCKLE)
The Big Bang Theory Season 4, Episode 18
(RAJ AND BERNADETTE CHUCKLE)
The Big Bang Theory Season 10, Episode 13
(BOTH CHUCKLE)
The Big Bang Theory Season 10, Episode 15
(nervous CHUCKLE)
The Big Bang Theory Season 5, Episode 23
[both CHUCKLE]
The Big Bang Theory Season 12, Episode 2