A forthcoming book about the Kennedy family is alleging that the late Jacqueline Kennedy Onassis fought to nip in the bud a particular problem in her Cape Cod garden.

In the book "White House by the Sea" by Kate Storey, the former first lady learned that marijuana was growing in her garden, much to her horror.

According to an excerpt obtained by Town & Country, it was around 1975 when Kennedy's assistant noticed some of the family members poking around in the garden, which piqued her interest. After realizing she had stumbled upon something nefarious, she told former police chief Jack Dempsey, who frequented the property with the Secret Service

Neither her assistant, Kathy McKeon, nor Dempsey believed the gardeners were responsible, so they told Onassis about their discovery.

Jackie Kennedy looks to her left in a light green outfita

Jackie Kennedy was reportedly shocked to learn that marijuana was growing in her garden on Cape Cod. (Michael Ochs Archives)

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"Are you kidding me?" she allegedly said to McKeon, who told her the news directly. "Oh my God, this can’t get out. How are we going to fix this?."

McKeon led her to Dempsey, and the former officer told Onassis, according to the book, "Just ignore it… we'll pull it."

Jackie Kennedy leans back on a balcony in Hyannis Port

Jacqueline Kennedy is pictured at the Kennedy compound in Hyannis Port, Massachusetts, in June 1953. (Hy Peskin Archive)

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The book said she was satisfied with this and replied, "Good… I don't want this to get out."

Later that day, Dempsey and the Secret Service destroyed the plant. Neither of Onassis' children, Caroline and John, were suspected of planting the marijuana.

A representative for her only living child, Caroline Kennedy, the U.S. ambassador to Australia, did not immediately respond to Fox News Digital's request for comment nor did the John F. Kennedy Foundation.

John F. Kennedy and Jackie walking towards the house in Hyannis Port

Sen. John F. Kennedy and his fiancee, Jacqueline Bouvier, walk up to the Kennedy home circa 1953. (Hy Peskin Archive)

The book divulges stories of the Kennedy family in their oasis – Hyannis Port, Massachsuetts

The late President John F. Kennedy and his family were known to spend many summers in the area. Following Kennedy's death in 1963, his wife continued to go there after her second husband, Aristotle Onassis, died in 1975.

John F. Kennedy has Caroline on his lap sitting and looking out on the Cape with Jackie

John F. Kennedy and Jacqueline Kennedy enjoy Cape Cod with their daughter, Caroline, in 1960. (Bettmann)

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Onassis thoroughly enjoyed her time on the Cape, inviting extended family on a regular basis. According to the book, the beloved Onassis enjoyed sunbathing nude and painting in her sunroom.

"Jackie O," as she was famously known, died in 1994. She was predeceased by both of her husbands and another son who died as a newborn, Patrick Bouvier Kennedy.