Thomas Kingston and Lady Gabriella Windsor attend the private view for “Gabrielle Chanel. Fashion Manifesto” on Sept. 13, 2023 in London.

Lady Gabriella Windsor is speaking out for the first time about the sudden death of her husband, Thomas Kingston, who died in February at age 45.

On Dec. 3, Lady Gabriella, who is a second cousin to King Charles, broke her silence during an inquest at Gloucestershire Coroner’s Court, revealing the circumstances surrounding her husband’s death. A spokesperson for the coroner’s office previously told PEOPLE that Kingston’s cause of death was “traumatic wound to the head.”

A gun was found near his body at his parents’ home in the Cotswolds. In her emotional witness statement, Lady Gabriella, 43, expressed her belief that her late husband’s “impulsive action” was likely triggered by medication he had been taking in the weeks leading up to his death.

“It appears to me Tom’s impulsive action was likely provoked by an adverse reaction to the medication he had been taking in the last two weeks of his life,” Lady Gabriella said in a witness statement read aloud in court, according to The Telegraph.

Lady Gabriella, who openly sobbed during parts of the hearing, described her marriage as one of deep love and trust, emphasizing that her husband had never expressed any suicidal thoughts, either to her or to others, according to Hello!.

“[Work] was certainly a challenge for him over the years, but I highly doubt it would have led him to take his own life, and it seemed much improved,” her witness statement continued, according to Hello!. “If anything had been troubling him, I’m positive that he would have shared that he was struggling severely. The fact that he took his life at the home of his beloved parents suggests the decision was the result of a sudden impulse.”

She added: “The lack of any evidence of inclination it seems highly likely to me that he had an adverse reaction to the pills that led him to take his life. I believe anyone taking pills such as these need to be made more aware of the side effects to prevent any future deaths. If this could happen to Tom, this could happen to anyone.”

The court heard that Kingston was prescribed zopiclone to help with trouble sleeping and sertraline for anxiety by his general practitioner, Dr. Nicky Naunton Morgan, who is also an apothecary (pharmacist) to King Charles and Queen Camilla’s household, The Telegraph reports. Kingston reportedly stopped taking the sertraline after a short period because it made him “very anxious,” and his prescription was later changed to diazepam and citalopram. He also reportedly “doubled” his dosage of sleep medication.

A financier and former hostage negotiator, Kingston was Lady Gabriella’s husband of four years when he died on Feb. 25, 2024. He previously dated Kate Middleton’s sister Pippa before marrying Gabriella, the daughter of Prince Michael and Princess Micahel of Kent, in 2019, and the couple frequently attended royal family events.

The coroner accepted on Dec. 3 that Kingston died as a result of “a self-inflicted gun shot to the head” and his father, Martin, “broke down” as he recounted the painful memory of finding his son’s body. The outlet said that the elder Kingston claimed “it cannot be a coincidence” that his son died three weeks after he began taking medications for insomnia and anxiety. While only caffeine and low levels of of zopiclone (a sleeping pill) were found in Kingston’s blood and urine in an autopsy, the late financier’s father alleged that sertraline could continue to affect a person’s thinking after it passed through their system.

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The court learned that father and son were licensed gun owners, and Kingston was found alongside one of his father’s guns he returned that weekend after borrowing it for a shoot. He was said to be “in his usual ebullient spirits” the day before he died, and attended his niece’s birthday party.

Buckingham Palace announced the news of Kingston’s death on Feb. 27, and Prince William attended his private funeral the following month.

The inquest is ongoing.

If you or someone you know is considering suicide, please contact the 988 Suicide and Crisis Lifeline by dialing 988, text “STRENGTH” to the Crisis Text Line at 741741 or go to 988lifeline.org.