Isabella is the sister of Fast And Furious actress Jordana Brewster and has previously dated actors Brandon Cooper and Milo Ventimiglia.
Radar Online is reporting that the brunette has recently left her job as a talent agency at Creative Artists Agency.
An unnamed source has told The Mirror: "As well as dating famous men before, Isabella just recently left her job as a talent agent so she'll be completely in her comfort zone with Russell.
"Although aside from the fame, her and Russell have a lot in common. They are both in recovery and totally into yoga.
"They are really enjoying spending time together. Isabella knows Russell is a ladies' man so she is trying to play it cool."
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