When a subspace of normal spaces is normal

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It is well known that a closed subspace of a normal space is normal. I am looking for a condition $*$, such that the following statement is true.

A subspace of a normal space is normal if and only if it has $*$ condition.

By a normal space, we mean a Hausdorff space that any two disjoint closed subsets contained in two disjoint open subsets.

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You are looking for "completely normal space":

"A completely normal space or a hereditarily normal space is a topological space X such that every subspace of X with subspace topology is a normal space. It turns out that X is completely normal if and only if every two separated sets can be separated by neighbourhoods." - Wikipedia

and here is a proof.