Model Behavior? Gigi Hadid Plays Mean Girl To Lisa Rinna's Daughter Amid Zayn Breakup

Yolanda Hadid and Lisa Rinna became bitter enemies after Lisa accused her former Real Housewives of Beverly Hills costar of faking her Lyme disease issues last season. Now RadarOnline.com can exclusively reveal their kids are doing a good job of picking up the battle where the moms left off!

According to a source, there’s a “fierce rivalry” raging between Yolanda's daughter — Gigi, 22 — and Lisa's girl — Delilah, 19.

"Gigi had massive falling out with her friend and assistant Cully Smoller when she confronted him after learning he had been hooking up with Delilah,” said the source.

“Gigi considered it a massive betrayal because she considers Delilah to be a rival in the modeling world,” the source explained. “She was concerned that Cully was giving Delilah information about what modeling jobs she was booking or being considered for. It has created a ton of drama.”

“The girls often are competing for high profile modeling jobs,” continued the source. “Gigi goes ballistic whenever anyone mentions Delilah, because she feels that she is trying to steal modeling jobs from her.”

The source noted that “Gigi's ego has gotten absolutely out of control” and there are concerns the model’s bad attitude will only get worse after her recent breakup with longtime boyfriend Zayn Malik.

While the source notes Lisa, 54, and Yolanda, also 54, “will be civil to each other in public,” behind the scenes the two “are absolute fanning their daughters’ rivalry.”

“Lisa was thrilled when Delilah began hooking up with Cully because she knew Gigi would hate it.”

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