To which age is a child's urine not considered impure to invalidate Wudhoo’ (ablution)? Thank you.

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The majority of scholars are of the view that a suckling male child's urine is impure. This is stated by An-Nawawi . Nevertheless, that impurity is considered light as long as the child does not yet eat. This means that sprinkling water over the stained part is enough to render it pure and there is no need for washing. When the urine of such a child stains either one's body or clothes, this does not invalidate Wudhoo’. 

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