Nick Reiner’s Former Yoga Teacher Calls Rob and Michele ‘Parents Doing Their Best’ (Exclusive)

Nick Reiner’s issues as a child were “beyond any of us,” says his former yoga teacher. 

Alanna Zabel, an instructor and wellness expert who taught the late Rob and Michele Reiner and their children yoga in private lessons in the early 2000s, tells PEOPLE that the filmmaker and his producer wife “were incredibly passionate, all-in parents doing their best,” and that their deaths on Sunday, Dec. 14, were “shocking.” 

Nick, now 32, “was notorious” for making sessions attended with his mother difficult, recalls Zabel, who taught the Reiner family until 2010. “We never could get through one single yoga session without Nicky barging in and having an intense issue or meltdown, and it would really break up the flow of a yoga class.”

Rob, 78, and Michele, 70, were found dead in their Los Angeles home on Sunday. Nick was soon arrested and charged with two counts of first-degree murder in connection with his parents’ deaths. Their other children, Jake and Romy, spoke out about the “horrific and devastating loss” in a statement shared on Wednesday, Dec. 17. “Words cannot even begin to describe the unimaginable pain we are experiencing every moment of the day.” 

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After years of group lessons, Rob and Michele asked Zabel to “teach Nicky privately, which I started to do, to help him to calm down and channel his energy,” she recalls. Nick showed progress in those one-on-one yoga lessons, inspiring Zabel to write the first of many children’s books: A Chair in the Air, featuring an overly energetic young character named Nicky who, as the author says, “learns how to regulate his emotions a little bit more and just to be more accountable for his behaviors.”

Zabel calls Nick’s childhood issues “a perfect storm… one of those things where, as hard as they tried to manage it, get help, address it, it’s just beyond any of us to be able to diffuse.” 

Michele was a “very, very passionate” mother, adds Zabel. “She lived for those kids… She was just very gracious and lovely.”

Nick appeared in court on Wednesday, Dec. 17, when his lawyer, Alan Jackson, declined to enter a plea for his client. The Being Charlie screenwriter’s arraignment will continue Jan. 7.

In PEOPLE’s latest cover story, another insider closer to the Reiners said the tight-knit family “could never reach stability” when it came to Nick’s issues. “They tried everything — giving him space, keeping him close — but his struggles are so deep… They were such lovely people and tried in every way to help their son.”