<P> Gibbs' relationship with Ziva has been called that of a surrogate father figure by executive producer Gary Glasberg, a tendency that intensified after she severed contact with Eli David following her return from Somalia . Cote de Pablo explained, "(Ziva's) got what I think you could call anger issues . She thinks she's been betrayed by her family, particularly her father . That's a big deal to her . Which would also explain her love and relationship with somebody like Leroy Jethro Gibbs ." Ziva seems to be more willing to show her vulnerability to Gibbs than to most of the other characters, and Michael Weatherly suggested in 2012 that she might have become something of a "hellcat" without Gibbs' guidance . Additionally, Ziva and Gibbs share several characteristics: they both rarely show emotion, speak several languages, and are extremely skilled at what they do . Though she often finds it difficult to follow his orders due to the autonomy she had as a Mossad control officer, Ziva looks up to Gibbs as a leader and often restrains herself from resorting to her assassin background in situations where he would not approve . He often uses this background to their advantage, however, by choosing her to interrogate certain suspects . </P> <P>--Cote de Pablo, 2009 </P> <P> Of all her relationships with the team, Ziva and Gibbs' has undergone the most growth . Initially, Gibbs distrusts Ziva as she is Ari Haswari's control agent . Ziva also bears the brunt of Gibbs' anger after Caitlin Todd was murdered . Ziva ultimately kills Ari, who was also her half brother, in order to save Gibbs' life . This event serves as the initial foundation for their relationship, and Gibbs takes responsibility for Ari's shooting in order to spare Ziva further pain . </P> <P> There is still tension, however, stemming both from NCIS director Jenny Shepard's decision to add Ziva to the team without consulting him and Ziva's habit of occasionally calling on Shepard, with whom she had a close relationship, to obtain key information in a case without going through regular channels (as seen in the Season 3 episode "Head Case"). However, this tension is lessened in the conclusion of the episode "Silver War" after Ziva saved Ducky's life . Ducky later tells Gibbs, "You took to Ziva more quickly than to any other agent before her . Timothy, Caitlin, even DiNozzo . I've always sensed there's a strong bond between the two of you . Something shared perhaps ." </P>

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