This study is a multicentric, randomized, parallel group, open label controlled trial of children age 1 year up to 4 years with new onset, idiopathic nephrotic syndrome. It is designed to test the initial duration of steroid therapy of either 3 month or 6 month total duration. Participants will be randomized to either extend their pre-trial 3 months (12 weeks) of standard of care corticosteroid therapy to add an additional 12 weeks of therapy or to stop therapy. Pre-trial standard of care corticosteroids will include 60 mg/m2/day for 6 weeks followed by 40 mg/m2/day every other day for 6 weeks of prednisolone or equivalent. The trial intervention will therefore be an additional 12 vs 0 weeks of corticosteroids in these children with idiopathic nephrotic syndrome.