They stretch well and I believe they will last the life of the product. They should last long enough for the child to outgrow them and, with proper treatment, may even become useless to another child. The material is a bit thin so I would consider them for spring/summer/fall but probably not for cold winters unless used as part of a layered outfit. They are inexpensive and a good lightweight choice for this type of pants. 4 star product.
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