The rescue search for Maeve Kennedy Townsend McKean and her son Gideon has been suspended with the pair tragically presumed dead.
“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 a lengthy and emotional Facebook post.
“The search that began yesterday afternoon went on throughout the night and continued all day today,” he said. “It is now dark again. It has been more than 24 hours, and the chances they have survived are impossibly small.”
“It is clear that Maeve and Gideon have passed away,” he said, adding that the search for their recovery will continue.
David then offered more insight into the canoe accident, which occurred on Thursday, April 2, at Maeve’s mother’s waterfront property in Shady Side, Maryland.
“We were self-quarantining in an empty house owned by Maeve’s mother Kathleen on the Chesapeake Bay, hoping to give our kids more space than we have at home in DC to run around,” David explained. “Gideon and Maeve were playing kickball by the small, shallow cove behind the house, and one of them kicked the ball into the water.”
The pair got into a canoe to retrieve the lost ball — and despite the protected cove, which David said has “much calmer wind and water than in the greater Chesapeake,” Maeve, 40, and Gideon “somehow got pushed by wind or tide into the open bay.”
An onlooker on shore spotted them about 30 minutes later, alerting the police.
That was the last time they were seen, and the canoe was found capsized miles away by the Coast Guard around 6:30 p.m. Thursday, with no sign of Maeve or Gideon.
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David went on to give heartfelt tributes of both his wife and son.
Of 8-year-old Gideon, David said he was a “deeply compassionate” boy and “incredibly social, athletic, and courageous.”
David called Maeve his “everything.”
“She was my best friend and my soulmate,” he wrote. “I am terrified by the idea that this will fade over time. You could hear Maeve’s laugh a block away—and she laughed a lot. She was magical—with endless energy that she would put toward inventing games for our children, taking on another project at work or in our community, and spending time with our friends.”
David and Maeve shared two more children, Gabriella, 7, and Toby, 2 1/2.
“Gabriella is heartbroken, but she amazes me with her maturity and grace,” David said of the daughter Maeve left behind, adding of Toby, “he’s still his usual magical and goofy self. I know soon he will start to ask for Maeve and Gideon. It breaks my heart that he will not get to have them as a mother and brother.”
In a statement to PEOPLE, Maeve’s mother, Kathleen Kennedy Townsend, confirmed that “the search for my beloved daughter Maeve and grandson Gideon has turned from rescue to recovery.”
“Maeve was vivid. You always knew when she was in a room. Her laughter was loud, unabashed, and infectious. She did everything with her full self and her whole heart,” Kathleen said of her daughter, who was also “devoted her life to helping society’s most vulnerable”
“She gave the best hugs, sang loudly and out of tune, danced, wrestled, argued, forgave. Maeve shone. 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.”
Gideon, Kathleen said, was just like his mother — “a star athlete who loved soccer, golf, and running.”
“He took after his parents in the most extraordinary ways. He loved riddles, math, chess, and adventures. He loved to invent new games with his mom and share them with us all.”
Maeve is one of slain Sen. Robert F. Kennedy’s granddaughters and a great-niece of former President John F. Kennedy. Kathleen reflected on her father RFK’s death at this sad time.
“When my uncle Ted eulogized my father, he offered a prayer that what daddy was to his family, and what he wished for others, would someday come to pass for all the world. This is our prayer for Maeve and Gideon,” she added.
“Our hearts are crushed, yet we shall try to summon the grace of God and what strength we have to honor the hope, energy and passion that Maeve and Gideon set forth into the world. My family thanks all for the outpouring of love and prayers as we grieve and try to bear this devastating loss.”
In a statement Friday, the Coast Guard said that it was a “difficult” decision to suspend its active search, which covered a “combined total of 3658 square miles over air, sea, and land over a period of 26 hours.”
“This was a difficult case, and even more difficult to make the decision to suspend the search,” Cmdr. Matthew Fine said. “Our crews and partners did everything they could to find them. We’ve kept the family informed at every step during the search, and our thoughts are with them tonight.”
• With reporting by ADAM CARLSON