Clothing & shoes for young children have been VAT free since 1973, but this is restricted to clothes meeting certain size criteria, or that are designed for under 14s. Where it can be proved clothes or shoes are bought for someone aged 16 or under, any such purchases should be VAT free.
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My son, and other young people I know, are all 11 and now in ‘adult’ sizes clothes & shoes. They are not the only ones. Penalising parent of children who no longer fit children's sizes is unfair and further impacts low income families. The speed that children grow can push many into debt. An inability to provide what a child needs quickly can result in bullying. Asking for VAT free on clothes bought for anyone aged 0-16 is not unreasonable, especially if age can be evidenced at time of purchase.