Why do cats groom each other? Research found that it is not always friendly

Cats are the most popular companion animals worldwide, and many people have multiple cats at home.

In these multicat households, not all the cats get along equally well.

Until recently, it was thought that if a cat licks another cat (a behavior known as "allogrooming"), the two cats were friends.

But is this really true?

Researchers at Ghent University and the University of Lincoln have investigated this behavior. ...