Linus from the “Peanuts” comic strip loved his blanket.

Even a determined beagle named Snoopy couldn’t pry it from him.

Now scientists are coming to grips with why some kids get so attached to a security blanket or a treasured toy.

These cherished objects actually take on lives of their own.

University of Bristol and Yale University researchers showed a scientific-looking apparatus to a group of three- to six-year-old children and told them the device was a sophisticated copying machine, capable of producing a replica of any object.

In reality, the scientists were like Linus’s sneaky sister Lucy. They were hiding behind a screen, making the toys seem to reappear as perfect copies.

But just as loyal Linus clung to his beloved blanket, these children weren’t parting with their treasured items without a ruckus.

A quarter of children flat-out refused to have their favorite object copied. Those who did place their comfort items into the machine demanded the originals back.

Scientists think some children believe their prized possessions have unique properties, or essences, that cannot be copied.

If you’re thinking this is kids’ stuff, the researchers point out that adults place huge value on original works of art and sports memorabilia, almost as if these objects contain some essence of the artist, athlete or historic moment.

Imagine trying to convince a sports fan to accept a replica in exchange for his authentic 1969 Amazing Mets autographed baseball.

It would be like trying to get Linus to give up his blanket.