Psoriasis can develop at any age. A third of psoriasis cases develop in childhood, but it more frequently begins between ages 15 and 25. Unfortunately, psoriasis is not a condition that children can “grow out of.” If you go an extended time without a psoriasis flare-up, you are considered to be in remission. Periods of remission commonly last between a month and a year, though in some cases, people have gone multiple years without a flare-up!