Gordon practices the flute : Season 13 Episode 91

Big Bird tries whistling like his fellow bird friend, but isn't getting the knack of it. Gordon encourages him to keep trying and assures him that with practice, he'll be able to whistle. Big Bird then sees Gordon's old flute, which he found stored away in the garage since he was young. He tries blowing a note to show how he's not able to play much anymore, but Big Bird spins Gordon's lesson back at him and has him keep trying.