Ronald E. Ostrin, who in January was named a court-appointed legal counsel for the proposed conservatee, provided the most substantial health update yet about the 77-year-old philanthropist, who has been married to Jay Leno for more than 40 years.

In a report filed by Ostrin in Los Angeles Superior Court on March 28, the attorney said that during his investigation into Jay Leno’s efforts to be a permanent conservator of his wife’s estate, he learned that Mavis has “major neurocognitive disorders,” “cognitive impairment” and “sometimes does not know her husband, Jay, nor her date of birth.”

Ostrin said in probate court documents — obtained Tuesday by The Times — that Mavis’ neurologist Dr. Hart Cohen told him that she “has a lot of disorientation” and “will ruminate about her parents who have both passed and her mother who died about 20 years ago.”

The doctor, who has been Mavis’ neurologist since treating her after a 2018 car accident, told Ostrin that “Mr. Leno loves his wife very much, and waited to bring this matter out of respect to her. [Cohen] said that Mr. Leno was ‘such a nice man and treats [Mavis] like gold.’” Ostrin wrote that he “reviewed substantial medical records which supported Dr. Cohen’s opinions.”

The attorney also described a Feb. 13 meeting at the Lenos’ Beverly Hills home where he spoke to the couple jointly and to Mavis privately to discuss “her wishes and desires about the proceeding and about her testamentary wishes.”

“Ms. Leno was a delightful person, and although it was clear she had cognitive impairment, she still has a charming personality and could communicate,” Ostrin wrote in the report. “She expressed a desire to vote and told me a little about her philanthropic work. She reposed great faith and confidence in Mr. Leno and relied on him for her protection and guidance.”

He affirmed that the Lenos, who have no children, “have a long-term loving and supportive relationship” and have “enough resources” to give Mavis “a safe and least restrictive environment, that she seems very happy with.”

The report also explained why the 73-year-old comedian is not currently seeking a conservatorship over Mavis’ person, a separate legal guardianship that would put the two-time Emmy Award winner in charge of medical and personal decisions for his wife. In speaking with Jay Leno’s attorneys and Mavis’ neurologist, Ostrin said he learned that Mavis “is already being prescribed medications for the care and treatment of major neurocognitive disorders (including dementia), and that those can continue to be prescribed without an order or personal conservatorship at this time.”

The purpose of Jay Leno’s petition is to prepare an estate plan, Ostrin said. And, if something were to happen to the comic, a petition “would promptly be filed according to the plans to be made” and a conservator of the person would be “appointed promptly,” Ostin wrote.

“Ms. Leno seemed very happy in their cozy environment,” he said. “However, no one lives forever, and the actions taken by Mr. Leno are necessary for his and Mavis’ protection.”

The court-appointed attorney said that “estate planning is something that most everyone needs, but by the time you need it, if you don’t have it, it is too late to get it.” He explained that Jay Leno’s petition to be a conservator of his wife’s estate is “designed to give Mavis that protection with the protection of court supervision,” confirming that she does not object.

“She consents to it and wants that. Mr. Leno is her protector and she trusts him,” Ostrin wrote. “Based on my interaction with Mr. Leno, plus some research I have done, he seems to be a standup guy and his private persona matches the public persona he projects.” (Ostrin footnoted “standup guy” to say “Pun not originally intended.”)

Jay Leno filed family court documents in January seeking a conservatorship so he can structure a living trust and other estate plans to make sure that his wife has “managed assets sufficient to provide for her care” should he die before her, according to a copy of the petition.

At the time, the petition said that Mavis “has been progressively losing capacity and orientation to space and time for several years” and that her husband “is fully capable of continuing support” for her physical and financial needs, “as he has throughout their marriage.”

The comedian’s original filing said Mavis’ “current condition renders her incapable of executing the estate plan” and that she is under treatment for “dementia and mood disorder.”

It is still unclear when when Mavis was diagnosed, but a doctor’s report from November, filed as part of the court proceedings, said she suffered from impairments to her memory, ability to concentrate and use of reason.

The documents said a conservatorship was needed to allow Jay Leno to execute estate plans that “will provide for Mavis and Mavis’s brother [who is] her sole living heir aside from Jay.”

“Jay Leno has always handled the couple’s finances through the term of their 43-year marriage, and will continue to do so until his passing,” the petition said.

The former late-night TV host told the Daily Mail later in January that he “just set up a will, in case something happens.”

Times staff writer Meg James contributed to this report.