Under what conditions should the orphan's wealth be commingled with the guardian's?

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If commingling the orphan's wealth is more beneficial and provides softer bread or better accompaniments (adum), it is preferable. This preference is based on the Divine command: {And they ask you about the orphans. Say, 'Making things right for them is best. And if you mingle your shares with theirs—they are your brothers. And Allah knows the corrupter from the one who makes things right. If Allah had willed, He could have put you in difficulty. Indeed, Allah is Exalted in Might and Wise} (Quran 2:220). The interpretation of 'He could have put you in difficulty' suggests constraint or hardship.