Certainly, the same
If parents encourage children when those insist on carrying identical clothes and possession of identical toys and, especially, if every time concede to children, they can become even more exacting over time.
Certainly, the same principle defines also the relations of parents with the only child: if parents are firm, children concede if parents hesitate, children argue.
You will help to develop consciousness of the identity and own taste if each of them has the box for clothes and if the identical clothes have labels with a name of the owner or a sign at twins.
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