Joe Kennedy, Andrew Cuomo and Family Members Mourn Deaths of RFK Granddaughter Maeve and Her Son

Benjamin VanHoose

The Kennedy family is grieving two of the family’s “brightest lights.”

On Friday, David McKean confirmed that his wife Maeve Kennedy Townsend McKean — the granddaughter of Sen. Robert F. Kennedy — and their 8-year-old son Gideon have been presumed dead. The two went missing in a canoe accident in Maryland.

“Despite heroic efforts by the Coast Guard and many state and local authorities, the decision has now been made to suspend the active rescue effort,” David wrote in an emotional Facebook post.

Her sister, Meaghan Kennedy Birdzell, shared family photos on Facebook in tribute to Maeve and Gideon, writing, “I love my sister Maeve and my nephew Gideon so much. So much love and prayers to David McKean and Gabriella and Toby ❤️❤️❤️❤️❤️.”

Rep. Joe Kennedy III, who is Maeve’s cousin, shared a tweet, telling his followers to embrace their loved ones. “We love you Maeve. We love you Gideon. Our family has lost two of the brightest lights. Grateful for the prayers,” he wrote, “Hold your loved ones tight.”

Maria Shriver, another cousin to Maeve, retweeted the politician’s tweet, writing, “So true ❤️.” She later tweeted, “My heart and love go out to my cousin @KKT_Kennedy and her family. There are no words. Please just pray for them.”

New York Gov. Andrew Cuomo, who was once married to Maeve’s aunt Kerry Kennedy, called the loss “emotionally very painful” during his Saturday press conference. “My daughter’s cousin has a tragedy, that’s just emotionally very painful,” he said. “They can’t hug each other and hold each other. They can’t even grieve together.”

Kerry also posted a photo on Instagram of David and Gideon, calling the father and son “inseparable.”

RELATED: Robert F. Kennedy’s Missing Granddaughter and Son ‘Have Passed Away,’ Heartbroken Husband Confirms

In a statement to PEOPLE, Maeve’s mother, Kathleen Kennedy Townsend said her daughter, 40, was “vivid.”

“You always knew when she was in a room. Her laughter was loud, unabashed and infectious,” said Kathleen, 68. “She did everything with her full self and her whole heart. She gave the best hugs, sang loudly and out of tune, danced, wrestled, argued, forgave. Maeve shone.”

Kennedy Townsend continued: “The fire emanating from her soul warmed us all. Her husband, David, and their children, Gideon, Gabriella, and Toby, were the great joys of her life. The role she treasured most was mom.”

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RELATED: ‘Please Pray’: Kennedy Family Speaks After RFK Granddaughter & Her Son Go Missing in Canoeing Accident

David — who also shared daughter Gabriella, 7, and Toby, 2, with Maeve — wrote on Facebook that Gideon was “deeply compassionate” and would spend hours “reading, learning everything he could about sports, and trying to decipher the mysteries of the stock market.”

“But he was also incredibly social, athletic, and courageous,” he continued. “… And he was brave, leading his friends in games, standing up to people who he thought were wrong (including his parents), and relishing opportunities to go on adventures with friends, even those he’d just met.

David added: “It is impossible to sum up Gideon here. I am heartbroken to even have to try. I used to marvel at him as a toddler and worry that he was too perfect to exist in this world. It seems to me now that he was.”