I'm wondering how close you are with your step-son if you are not comfortable enough to speak to him. If the relationship is already strained, then I would not add anymore fuel to the fire.

If they are paying the rent and everything else themselves, it's up to them how they want to live. And unless they were both raised in the woods, they obviously know what a clean house looks like.

If you ARE comfortable with taking your step-son aside and speaking to him privately, maybe just say you know it can be overwhelming to set up a new household and you would be willing to give them a hand.

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