The friendship is introduced in Consequently. They seemed to have been best friends since prior Pilot. Lexi and Mariana's brother, Jesus, start a secret relationship. When Mariana finds out, she gets angry with both of them due to being uncomfortable with the idea of her best friend and brother dating. Lexi tries to talk with her, but she doesn't forgive her for keeping it a secret. They make up in The Fallout.
- They're seen walking and talking together.
- At the cafeteria, Mariana and Lexi talk with Kelsey about Callie.
- Lexi comes to visit Mariana at her house.
- Mariana interrupts Lexi and Jesus after they kiss.
- Mariana notices some interaction between Jesus and Lexi.
- Mariana asks Jesus if he has something to do with her.
- Lexi tries to convince Jesus to keep on with their relationship, no matter what Mariana thinks.
- Lexi is part of Mariana's court.
- Lexi and Lena help Mariana with her quinceañera dress.
- Lexi and Mariana talk after Mariana tries her dress.
- Lexi is at Mariana's home.
- Mariana and Lexi talk at Mariana's room.
- At the party, Lexi gives Mariana her birthday present, and later hug.
- Mariana finds out that Lexi and Jesus have a relationship.
- Mariana gets angry with them.
- Lexi dances at the party with Mariana's court.
- Lexi tries to talk to her, but she doesn't forgive her.
- When Mariana and Jesus are watching their video at the party, Mariana looks at Lexi and she smiles to Mariana.
- Mariana is still angry at Lexi - she doesn't want her around.
- Mariana and Lexi are seen at Wyatt's old house.
- Mariana and Lexi are seen in the house talking to Lexi's parents.
- Mariana and Lexi are seen in the hallway when Mariana asks what's going on between her and her brother.
- Lexi tells Mariana about her grandmother and how they may be going back.