CHRIS CARLSON / Invision/AP 1 / 7
CHRIS CARLSON / Invision/AP 1 / 7

Jeff Conaway's on-off girlfriend Vikki Lizzi has vowed to challenge a restraining order keeping her away from the ailing actor as he fights for his life in hospital.

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The "Grease" star, who played bad boy Kenickie in the hit musical, was admitted to the Encino-Tarzana Regional Medical Center in California on May 11 and is battling pneumonia and sepsis, a potentially fatal blood poisoning caused by a bacterial infection.

RELATED: Dr. Drew says Conaway did not OD on drugs

Conaway was placed in a medically-induced coma to aid his recovery, but his partner Lizzi has reportedly been banned from approaching the actor and his family by his relatives, who obtained the protective order last week.

Lawyers for Lizzi are heading to court to ask a judge to relax the ban and allow her to visit Conaway in hospital, according to

RELATED: Read more about Jeff Conaway on MSN

Her friend Aubry Fisher tells the website, "Vikki just wants to take care of him, she would never hurt him in any way."