Why do some people sleep with a blanket in summer

Some people sleep with a blanket even in hot weather because it makes them feel protected against anything that might touch them while they're asleep.

Some people were conditioned ever since they were children to sleep with a blanket. This habit could stay with them even in their adulthood. 

The body temperature drops at night while a person is sleeping, which makes some people feel cold and in need of a blanket. 

Studies have shown that sleeping with a blanket raises seratonin levels while a person is asleep, which makes a person feel calm and happy. 

Some people sleep without any clothes on and use a cotton blanket to cover themselves at night for security. 

Some people cover themselves up with a blanket even in hot weather to protect themselves from any insects that might be there.