With the aid of a walker, Sister Rita Callanan inches through a doorway to a sitting room in the convent where she lives on her own in South Los Angeles.

Sister Rita’s constant companion in the convent is Princess, a 19-year-old cat hard of hearing and blind in one eye.

The phone on the wall of Sister Rita’s kitchen rang continually. In recent days, the parish office at St. Bernadette’s Catholic Church has been flooded with calls from the media.

But Sister Rita hasn’t been taking calls. At 79 years of age, she remains in active ministry at St. Bernadette’s, despite assorted health problems including diabetes and breast cancer. But what truly ails her nowadays is the recent death of her friend and fellow sister in the Order of the Sisters of the Most Holy and Immaculate Heart of the Blessed Virgin Mary.

Earlier this month, 89-year-old Sister Catherine Rose Holzman collapsed and died during a court proceeding in downtown Los Angeles.

As two of the last five living sisters of the Immaculate Heart, Sisters Rita and Catherine Rose were embroiled in a legal saga that could only happen in Los Angeles. The nuns claimed that the Archdiocese of Los Angeles was attempting to sell a convent that belongs to them to pop star Katy Perry for a cool $14.5 million.

With Sister Catherine Rose’s death on March 9, Sister Rita became the lone holdout who remains opposed to the sale.

“Sister’s death has taken a toll on me. It really has,” she said. “But I’m not going to give up.”

The convent in question is an estate seemingly made for a chart-topping superstar—a breathtaking Mediterranean-style villa perched on 8 acres in the tony hills of the Los Feliz neighborhood with a fountain, pool, and commanding views of the San Gabriel Valley and downtown.

It was built in 1927 by architect Bernard Maybeck for businessman Earle C. Anthony. The sisters purchased the property in 1972 at a favorable price of $600,000 from Sir Daniel Donohue, who had been the owner since the early 1950s. The nuns bought the property by pooling income they earned as educators in the parochial schools of Los Angeles.

“To us it is holy ground,” Sister Rita said.

The property dispute boils down to which party had the authority to sell. Sisters Rita and Catherine Rose have said they are the rightful owners and that the archdiocese put an end to retreats and other sources of revenue, evicted the sisters, and took over the convent.

The archdiocese says it became too costly for the retired sisters to remain living on the property and that it no longer accommodated their physical needs.

“There are a lot of stairs, and it’s a really big space as well,” said Adrian Alarcon, a senior spokesperson for the Archdiocese of Los Angeles. “A lot of the sisters now live in assisted living homes or retirement homes where they can get the proper care they need.”

Sister Rita says the Vatican approved an agreement in 1992 that guarantees every nun in the order be taken care of “down to the very last sister.”

“We would be living there and have spiritual, and if necessary, physical help,” she said.

McKool Smith Hennigan, the law firm that represents the Archbishop of Los Angeles, José Horacio Gómez, said in a statement: “A majority of the Immaculate Heart of Mary Sisters agreed to have the Archbishop sell their former convent on their behalf in 2014 with all proceeds going to the Institute for the care of the Sisters.”

A company owned by Perry had already made a cash offer that was approved by the archbishop, according to the statement.

For her part, Katy Perry has said she intends to live at the estate with her mother and grandmother. At a meeting in 2015, Perry told the sisters that she wants to “sit in the meditation garden, sip green tea and find herself.”

Sister Rita put the onus on the archbishop, but said she wished the singer would relent: “I just feel that Katy Perry is used to getting all she wants, and to her money means everything, and to her, whatever Katy wants, Katy gets.”

Sister Rita says she learned of the planned sale from friend who is a realtor in Los Feliz. She says Archbishop Gómez planned to sell the estate to Perry without consulting with the sisters.

But the nuns beat the archdiocese to the punch. They invited restaurant owner Dana Hollister to buy the property from them, which she did, with plans to convert the estate into a boutique hotel.

In Los Angeles, canon law requires a sale of church property worth more than $7.5 million to get approval from the Vatican. L.A. County Superior Court Judge Stephanie Bowick later invalidated the sale, writing that it lacked approval from the pope, the Holy See, or the archbishop.

A jury sided against Hollister last year and she was ordered to pay $5 million in damages, an amount that led the erstwhile buyer to file for bankruptcy.

“I think it’s unconscionable that the archbishop is trying to get $15.5 million from Dana Hollister,” Sister Rita said. “The archbishop has put Dana Hollister into bankruptcy.”

The archdiocese and its attorneys argued that Hollister had taken advantage of the elderly nuns, which Sister Rita denied. The nuns signed the property over to Hollister for a payment of $44,000, with Hollister agreeing to pay $9.9 million over three years. The archdiocese argued successfully in court that the promissory note was nonbinding and, therefore, fraudulent.

“We were never allowed to tell our story,” Sister Rita said. “The jury never heard our story. I would have liked the jury to have heard that we were the ones who asked Dana to buy the property and she was trying to help us out.”

She said she and her attorney are planning out their next steps. And though she was mum on details, she seemed determined to take a more active part moving forward.

Though Archbishop Gómez has pledged to take care of all of the IHM sisters for the rest of their lives, Sister Rita says her stipend was reduced and she got a cancellation notice from a health insurance company after a bill was left unpaid by the archdiocese.

“When the archbishop says he is taking care of us, I say I got a notice of cancellation of service. Do you say that is taking care of us? I say no.”

For her service to the parish where she lives, the archdiocese pays for Sister Rita’s rent and bills, and for a housekeeper. But she says she fears there may be negative consequences to continuing to oppose the archbishop.

She has started a Go Fund Me to continue the legal fight and prevent the sale of the convent to Katy Perry. “It is now more important than ever to continue this fight and for our cause to prevail,” she wrote.

She said other Catholic orders would do well to heed the fate of the Sisters of the Immaculate Heart. “I say to the brothers and sisters about this case, please watch carefully because if our archbishop can take our property away from us and our money then it can happen to you.”