Mental illness is when something is wrong with our brain and it affects how we feel, think, and act. Sometimes it makes it hard to do everyday things like going to school or work. Mental illnesses can be caused by different things, like a life event or family history. Some mental illnesses include depression, anxiety, or schizophrenia. Mental illnesses can also get worse if not treated. Treatment for mental illness can include going to therapy, medication, or joining a support group. With help, many people can learn to manage their mental illness and can live happy and healthy lives.