Kennedy shared photos of himself and his grandchildren on Sunday afternoon, posing and playing in the water in Rock Creek.
"Mother’s Day hike in Dumbarton Oaks Park with Amaryllis, Bobby, Kick, and Jackson, and a swim with my grandchildren, Bobcat and Cassius in Rock Creek," he wrote on X.
The kicker: the National Park Service forbids swimming at Rock Creek due to elevated bacteria levels in the water.
"Rock Creek has high levels of bacteria and other infectious pathogens that make swimming, wading, and other contact with the water a hazard to human (and pet) health," according to FOX.
"All Rock Creek Park areas are closed to swimming, bathing and wading by people and pets," the NPS website states.
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