In the entertainment industry, as in diplomacy, often what is not said can be a better indication of character than what is. Witness the former actress Meghan Markle, who, by marrying Prince Harry, became Duchess of Sussex, and who is so far refraining from public comment following the death, apparently by suicide, of her co-star Billy Miller, who “surrendered his life” after a long battle with mental health issues.

The silence is all the more striking because the duchess, who’s presently struggling to maintain the stardom and prestige she and the Duke have sought for themselves in Southern California, has positioned herself as a mental health advocate.

Alongside Prince Harry, who’s made mental health the cornerstone of his charitable efforts by speaking at length about the traumas he has endured as the “spare heir” to the British throne, Meghan has gone so far as to claim she contemplated suicide while a captive of Kensington Palace and the “men in gray suits” who — cruelly, apparently — run the Royal Family.

According to a statement that Mr. Miller’s mother, Patricia Miller, issued on Monday, her son had “fought a long hard valiant battle with bipolar depression for years” and that he “loved his family, his friends and his fans but in the end the disease won the fight and he surrendered his life.” Mr. Miller’s manager had stated earlier that the actor “suffered with manic depression” before his death.

Mr. Miller had a recurring role on “Suits,” the USA Network television series, which aired between 2011 and 2019 and in which the future duchess had a starring role. Reruns of “Suits” have in recent weeks become a massive hit on Netflix, with millions of viewers playfully posting on TikTok how they can mindlessly watch the thought-free show without having to give it any real attention.

Mr. Miller died on Friday at the age of 43. By Tuesday, Ms. Markle — now 42 — had said nothing, at least not publicly, about the death of Mr. Miller. 

The actor also appeared in multiple episodes of the long-running soap operas “The Young and the Restless” — for which he won three Emmy Awards —  and “General Hospital,” among appearances in numerous other television shows.

To what extent Mr. Miller and Ms. Markle maintained a friendship, if any, after the conclusion of “Suits” was not immediately clear. Yet following the new twists in her life following her marriage to the Duke of Sussex, the former actress experienced different kinds of pressures that, by her telling, were sometimes intense.

In a 2021 interview with Oprah Winfrey, Meghan Markle said that at one point the stress of royal life made her feel like “I just didn’t want to be alive anymore.” 

In May, the Sussexes visited a youth group at Santa Barbara on the occasion of Mental Health Awareness month. According to the Sussexes’ Beverly Hills-based foundation, Archewell, the hour-long visit aimed to help them “learn firsthand about this generation’s experiences with social media and societal pressures, and how it affects their mental well-being.” 

The Sun asked the Archewell Foundation for comment from Ms. Markle about Mr. Miller’s passing but, as of Tuesday, had not received a response. 

While it can be expected that the stress of royal life as lived at its source in Britain is lessened in Ms. Markle’s current home on the Coast, modern life is not without its strains. 

In August, the duchess was photographed at Montecito wearing a NuCalm anti-stress patch. The company, which has claimed it has no business relationship with the duchess, describes its “biosignal processing disc” as “a revolutionary delivery mechanism that activates the parasympathetic nervous system” and “increases the therapeutic value of NuCalm,” which the company says is a “mental help app.”

Meanwhile, on Sunday, “Suits” creator Aaron Korsh wrote on X, “Very sad news for the entire Suits family. I flew home once with Billy. We had a great time, bonding over the five-hour flight, which seemed like it was over in minutes. A funny, smart, kind, gentle man.”

The executive producer of “General Hospital,” Frank Valentini, paid tribute to the actor on X, saying “I am devastated to hear news of the incredibly talented Billy Miller’s passing. On behalf of the entire @GeneralHospital family, our hearts go out to his family and friends during this difficult time.”

On “Suits,” the legal drama that premiered on the USA Network, Ms. Markle played the role of a paralegal named Rachel Zane. In each of the five episodes of “Suits” in which Billy Miller appeared, he played the role of the brother of the character of Harvey Specter, who was played by Gabriel Macht.

As of Monday, Mr. Macht had not posted any comment on social media about Mr. Miller’s passing. Many other stars, however, did not hesitate. “Buffy” icon Sarah Michelle Gellar wrote on social media, “Rest in Peace Billy. It was an honor to work with you but more of an honor to know you.”

“I am speechless,” wrote Oscar-winner Octavia Spencer. “I’m laying here scrolling through IG and came across a post that we lost Billy Miller.”

“Too many feelings, but you are gone way too soon and I’m so happy I got to work with you all those years, but also call you a friend,” wrote the Selling Sunset star and soaps alumna Chrishell Stause. “I hope you are at peace now.”

So what could explain the silence from Meghan Markle?  Although she is famously aloof when it comes to social media, she is no stranger to the spotlight. The reasons, like so much else in the life of the busy duchess, could be a mix of personal and professional. 

“After her divorce from her first husband, Markle became protective of sharing her thoughts about other people,” says an industry source who met the former actress on more than one occasion during the time when she was still married to film producer Trevor Engelson.

The two were married between 2011 and 2014 while he was at Los Angeles and she was filming “Suits” at Vancouver. “She may also be doing the same here out of respect for Miller and his family’s privacy during this difficult time,” the source tells the Sun.

Over the weekend, Ms. Markle was in Germany, where she had flown from California to attend the Invictus Games along with Prince Harry. A documentary series about the sporting event executive produced by the Duke of Sussex has underperformed for Netflix, the streaming company with which the couple have signed a lucrative contract.