Jerry Lee Lewis is at the center of a legal battle over involving his children and his current wife. (Photo: Bang Showbiz)

Jerry Lee Lewis, the hard-living early pioneer of rock and roll, is at the center of a legal battle involving family members over allegations he’s being drugged by his seventh wife in an effort to control his substantial fortune.

The ailing, 81-year-old singer’s daughter, Phoebe Lewis-Loftin, has asked a court to ordered psychological tests to determined the singer’s mental state.

The daughter alleges that his current wife is controlling him by plying him with opiates.

The move comes after Lewis previously sued Loftin and her husband for defamation, elder financial abuse and fraud.

The suit was dismissed because it was filed in the wrong state.

The lawsuit charged Phoebe had kept her famous father sedated with a number of pharmaceuticals. While managing his affairs, she allegedly squandered millions of dollars on luxury cars, real estate and cosmetic surgery.

But Phoebe insists Jerry’s seventh wife, Judith Brown, is the one who is plying him with opiates to keep him in a vegetative state while she take control of his affairs, according to court papers obtained by pop culture Web site The Blast.

She also claimed their 2012 marriage is a sham because the singer was “incoherent and in a wheelchair” at the time.

Phoebe denies stealing from her father, according to the court papers. She says she’s seen records proving Brown bought the opiates.

“He is 81 years old and even though he has been and is an extraordinary talent and entertainer on the world-wide stage he has been mistreated, mislead, misdirected and to my belief drugged to the point that he lacked the capacity to make proper decisions.”