NCIS and began to threaten Abby for not sending in a report about the murder of Pedro Hernandez, Rivera's father, whom Gibbs had killed 20 years previously in revenge for Hernandez killing Gibbs' first wife, Shannon, and young daughter, Kelly. The entire team, including Ducky and Vance, ordered him to leave her alone and to not harass her, or to be escorted forcibly from NCIS Headquarters. Rivera eventually left of his own accord, but was later arrested for attempting to kill Gibbs and his father at a safehouse, and accidentally killing his sister, Paloma. Gibbs' concern for Abby's safety is such that he will even drop his trademark cup of coffee if she is in serious danger. Twice this occurred: in the episode "Kill Ari" when Ari shot at her while she was in her lab, the other time was in the episode "Driven" when she was trapped inside an experimental Humvee, which had been rigged to fill with exhaust fumes and suffocate its occupants. Ziva David Abby is portrayed as cold to Ziva David upon her arrival at NCIS as she, like the rest of the team, was still grieving over Kate Todd's death and the fact that Ziva was Ari Haswari's half-sister. Abby would scribble over pictures of Ziva and frequently mispronounce her surname to annoy her. Later, upset by Ziva's calm response to Gibbs being injured in a bombing, Abby slapped her. Abby eventually came around, and she and Ziva became good friends. This was solidified in the episode "Capitol Offense" when Ziva bought Abby a "chocoholic's choice" cupcake in gratitude for giving her a place to stay while her home was being fumigated for termites. After the cupcake unexpectedly vanished, Abby used her knowledge of forensics to prove McGee had stolen it, angering the rest of the team. Ziva flinched away from Abby's hugs at first, not understanding why she did so, but eventually came to accept them with more ease. In the season-seven finale, Abby was shown to be present at Ziva's citizenship ceremony, along with Ducky, McGee, and Jimmy Palmer. Later in the episode "Gone", the two bonded more when Ziva took in a teenaged girl who witnessed her father's murder and best friend's kidnapping as they both tried to help the girl feel at ease throughout the ongoing investigation. After Ziva's father was gunned down in "Shabbat Shalom", Abby was shown baking cookies