The Season 4 episode of "Blue Bloods" titled "Bad Blood" shocked audiences with the revelation that Maria's brother, Javi, is a suspect in a murder case. Maria and Danny start tailing Javi, and eventually, she confesses their relationship. The episode explores their complicated history and Maria's hope that he is not the killer. Audiences praised the storyline, appreciating the portrayal of the siblings' relationship and Javi's ultimate act of bravery. This episode sheds light on addiction issues, and resources for help are provided.