Robert F. Kennedy Jr. couldn’t have a snake in the grass.

The wildman Health and Human Services head once came charging over to a little kids’ birthday party after hearing that a snake was in a nearby garden, ripe for the taking, according to his sister.

While the innocent, unsuspecting children were busy enjoying the birthday party, RFK Jr., who lived a mile down the road, showed up armed with a pillowcase and a bedsheet, his sister Kerry Kennedy recounted.

“And he grabbed the snake and stuffed it into the pillowcase while he was holding his infant son. So that’s a little scary,” she told CNN’s “Erin Burnett OutFront” on Monday.

Kerry had called her brother over to take care of the serpent, which took place roughly 25 years ago. But she didn’t realize what she was in for.

RFK Jr. took the animal out while it “was just chomping on his hand” to show the children, before noticing a vole that he then snatched with his bare hands.

“Then he walked up to where the rest of the birthday party was, and he put that into the bag with the snake, which made all the kids scream because they were afraid the snake would eat the vole,” his sister recounted.

“So then he shoved his hand back into the pillowcase and grabbed the snake.”

The future HHS secretary later released the snake into a swimming pool where children were playing.

“This is somebody who, on the one hand, has a fascination with nature, but on the other hand has a lack of judgment when it comes to the safety and care of children,” she concluded.

RFK Jr. reacted to her tale by accusing her of “Trump Derangement Syndrome” and posting an image of them together in 1964 while he brushed his face on a bird.

The Kennedy scion has a long history of wild encounters with nature. Last month, he posted video of himself snatching two black racer snakes off Dr. Mehmet Oz’s patio, while his wife, actress Cheryl Hines, pleaded with him to be careful.

In April, it was revealed that RFK Jr. once pulled over on the side of the highway to chop the penis off a road-killed raccoon for unspecified future studies.

His daughter, Kick, once recounted how he raced over to Squaw Island in the Finger Lakes to decapitate a dead whale washed up on shore with a chainsaw and then strap the giant noggin to the roof of the family vehicle.

“Every time we accelerated on the highway, whale juice would pour into the windows of the car, and it was the rankest thing on the planet,” she recalled to Town & Country magazine.

RFK Jr.’s cousin, former first daughter Caroline Kennedy, alleged to lawmakers last year that the HHS boss would grind up baby chicks and mice in a blender to make food for his hawks.

She described his dorm room as “a perverse scene of despair and violence.”

One of his most famous excursions emerged in 2024, when he fessed up publicly to dumping a dead bear cub in Central Park and trying to make it look as though the furry mammal had been killed in a bicycle accident. 

RFK Jr. later posted photos of himself posing with the blood-soaked beast, in which he pretended that the dead cub was biting off his hand.