“Smell is the one sensory system that connects directly with the limbic system, which is the emotion, memory, and pleasure center of the brain,” says Biel. “It’s all about association, and kids often sniff things that conjure up pleasant memories that they find comforting.”

This swelling can be triggered by allergies (such as hay fever), irritants in the air (such as cigarette smoke, perfume or dust), and a viral infection (even before you have full-blown symptoms). People can also experience constant sniffling if they use a nasal spray to treat their allergies or cold symptoms.

Stopping a runny nose with home remedies