Garth Brooks is trying to hide a family secret from his fans - his sister Betsy Smittle is allegedly struggling with bipolar disorder and recently faced police arrest for streaking down her street.

Smittle, who performed alongside her little brother from 1989 to 1995, is still close with Brooks and he reportedly rushed to her Tulsa, Oklahoma home on April 26 when he learned she was acting strangely.

According to the Globe publication, Smittle, whose birth name is Harriet, suffered a mini-breakdown after a fight with her gay lover and ran naked out of the home they share.

Police confirm they were called to the scene by concerned neighbors, who feared Smittle was suicidal. A spokesman tells the publication, "She didn't exhibit any signs she was a danger to herself or others," and the authorities made no arrest.

According to the Globe, Smittle was hospitalized following the naked escapade. She underwent two weeks of psychiatric care and then readmitted herself to hospital after failing to resolve issues with her partner.

A friend tells the publication, "She (Smittle) told me they had trouble finding the right meds (medication) for her."

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(This news article provided by World Entertainment News Network)