We all have good ideas about some of the "pressures or strains" that can result in depression - but they are not all agreed upon and there might be others.
Depression in adolescents should be taken seriously. Youth suicide is the third most common cause of death in this age group.
It can be hard to distinguish adolescent turmoil from depression, especially as the young person is also forging new roles within the family and struggling with independence, as well as academic and career decisions.
There are many "pressures" in our children's lives and it is often unclear when the depression started. Much of the time its effect is gradual.