Tone is a choice. The same sentence can open a door or slam it.

Words carry less than people think; delivery carries the rest. The same question can arrive as curiosity or as an accusation depending on speed, volume and where you put the emphasis, and the person hearing it responds to the second thing almost entirely. Most fights that seem to be about content are really about a tone nobody named.

Before a conversation you know will be tense, decide the tone first and the words after. Slower and quieter than feels natural is usually right. It is the easiest lever you have, and it is entirely yours.