In a viral post on Reddit, u/Phishstyxnkorn shared a photo of a handwritten note stating: “You agreed to play this game so if you get hurt, you cannot tell on me.”

Underneath is a line signed by his younger sibling and the word “yes.”

The post has received over 25,000 upvotes, with many Reddit users seemingly familiar with the scenario.

The top comment has racked up 2,000 likes and says: “You hear a scream, and then hushed whispering.”

According to WebMD, there are health benefits to be gained from kids running, jumping, climbing and wrestling, such as helping them strengthen their bodies as their muscles and their lungs get a workout.

It can also help them release energy and get the hour of physical activity that doctors recommend for kids each day.

Pretending to fight can also help children learn important problem-solving skills. For example, when kids shout things like “that’s not fair!” or “time out!” it shows that they have expectations when they pretend to fight.

The American health and wellbeing website states play fighting works only because there’s some level of turn-taking and cooperation involved.

Siblings playfighting may be concerning for parents who worry about their children getting hurt but it is a normal part of childhood, so it isn’t surprising to see so many Redditors are familiar with the scenario.

User, TittyVonBoobenstein, said: “You hear a hushed but distinctly panicked ‘you promised, you promised!!’”

Redditor, u/1m2c00l4u said: “IF YOU SAY A WORD YOU BETTER LAWYER UP B*TCH.”

Another referred to little kids as the “most litigious” people in the world.

Older sibling, u/MatureUsername69 said: “And then the older one let’s out a very forced laugh to try to get the other one to chill. Then you’ll hear the older one say ‘you can hit me in the same spot 3x as much’ (70% success rate and it doesn’t matter because they’re small and weak). How do I know this? I’m the older one.”

Sharing an experience, beerscotch said: “I once power bombed my younger brother on the lino. I wish I had a contract to protect me on that one.”

Other users sarcastically wrote about the contract itself.

Redditor, Itsthenewvodka said: “It’s like the contract I signed when I entered the U.S. Navy.”

Newsweek has reached out to u/Phishstyxnkorn for comment. We could not verify the details of the story.