Sally Brown and Lucy van Pelt appear to be friends with each other, despite Lucy playing tricks and being mean to Sally.
In Is This Goodbye, Charlie Brown?, Lucy found Sally waiting in front of the house, saying that she was waiting for Linus to take her to the movie theater. Lucy told Sally that her family is moving, and that Linus was not coming, but Sally refused to believe this.
In the This Is America, Charlie Brown series premiere episode, "The Mayflower Voyagers", Lucy and Sally were patching up clothes and talking about the benefits of having Captain Standish as their captain despite not being a Pilgrim himself. When Lucy explained that among his good deeds was teaching them self-defense from the Indians, Sally became worried about today being the day they attacked because she had not even finished the wash yet.
In I Want a Dog for Christmas, Charlie Brown, Sally and Lucy told Rerun to leave the sandpit.
In January 2018, there was a performance that focused on Sally and Lucy called Lucy and Sally's Fiesta Fantasy in Knott's Peanuts Celebration.
In You’re a Good Man, Charlie Brown Lucy threatens Linus by saying that she will tell Sally what he said about her, to which Sally responds, “What did you say about me, Linus?”. Lucy is then seen whispering to Sally and tries to tell her what Linus said about her until Schroeder cuts her off. Afterwards, during the song “Glee Club Rehearsal”, Sally asks Lucy what Linus said about her and Lucy responds, “He said, he said you were…an enigma!”. Sally then screams, “Boy, that makes me…what a terrible thing to call a… Whats an enigma? Never mind!!” and storms off.