Kevin Mazur / WireImage 1 / 26
Kevin Mazur / WireImage 1 / 26

Amanda Bynes' parents aren't the only ones getting the silent treatment.

The troubled 26-year-old actress has also been ignoring Jennie Garth, who played her sister from 2002 to 2006 on the WB sitcom "What I Like About You." Us Weekly spoke to Garth, 40, at the ELLE Women in Hollywood event in Beverly Hills, Calif, on Oct. 15.

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"I tried reaching out to her and I haven't been able to reach her," said Garth, a single mother of three. "My heart feels for whatever she is going through, and I love her dearly."

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Bynes' agent, publicists and lawyer have reportedly jumped ship, while her dentist dad, Rick, and her office manager mom, Lynn, are helpless. "Amanda shut them out and isn't speaking to them," a source said in the Oct. 8 issue of Us Weekly.

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The actress hasn't worked since 2010's "Easy A" (she famously retired then "unretired" from acting via Twitter), and since then, her behavior has become increasingly erratic. Bynes' BMW was impounded on Sept. 16 after she drove on a suspended license (following an April DUI arrest and two alleged hit-and-runs). In recent months, she has been spotted muttering to herself in stores on both coasts.

"Amanda is out of control," one insider explained. "It's been slowly going on for years, but now it's getting really bad."

This article originally appeared on Usmagazine.com: Jennie Garth on Amanda Bynes: "I Tried Reaching Out to Her"

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