What Is Seasonal Affective Disorder? Seasonal affective disorder (SAD) is depression that happens only at a specific time of year. With SAD, a person becomes depressed in fall or winter, when days are ...

Medically reviewed by: Robyn R. Miller, MDThis link opens in a new tab Learn About Adolescent Medicine & Pediatric Gynecology at Nemours Children's HealthThis link opens in a new tab My friend and I ...

Medically reviewed by: Larissa Hirsch, MDThis link opens in a new tab Learn About Primary Care Pediatrics at Nemours Children's HealthThis link opens in a new tab When we breathe, the respiratory ...

What Are the Lungs and Respiratory System? The lungs and respiratory system allow us to breathe. They bring oxygen into our bodies (called inspiration, or inhalation) and send carbon dioxide out ...

Medically reviewed by: KidsHealth Medical ExpertsThis link opens in a new tab Learn About Primary Care Pediatrics at Nemours Children's HealthThis link opens in a new tab Every single person has a ...

What Are the Spleen and Lymphatic System? The spleen is located in the upper left part of the belly under the ribcage. It helps protect the body by clearing worn-out red blood cells and other foreign ...

Medically reviewed by: Larissa Hirsch, MDThis link opens in a new tab Learn About Primary Care Pediatrics at Nemours Children's HealthThis link opens in a new tab Help kids avoid anything they're ...

Medically reviewed by: KidsHealth Medical ExpertsThis link opens in a new tab Learn About Primary Care Pediatrics at Nemours Children's HealthThis link opens in a new tab The heart is a pump, usually ...

Our well-child checkup schedule lets you know how often kids should see a doctor, even when they're not sick. Read the articles below to find out what to expect at your child's next well-child checkup ...

Medically reviewed by: KidsHealth Medical ExpertsThis link opens in a new tab Learn About Primary Care Pediatrics at Nemours Children's HealthThis link opens in a new tab How do you remember the way ...

What Is the Digestive System? Food is our fuel, and its nutrients give our bodies' cells the energy and substances they need to work. But before food can do that, it must be digested into small pieces ...

Medically reviewed by: KidsHealth Medical ExpertsThis link opens in a new tab Learn About Primary Care Pediatrics at Nemours Children's HealthThis link opens in a new tab The endocrine system is made ...