It can help you communicate more effectively: When you're calm, you're more likely to choose your words carefully and communicate your message clearly. This can help prevent misunderstandings and ensure that the family member  understands your position.

It can help de-escalate the situation: If your family members becomes defensive or confrontational, staying calm can help prevent the situation from escalating further. By remaining composed, you can help keep the conversation on track and avoid any unnecessary conflict.

It can help you maintain control of the conversation: When you're calm, you're more likely to stay in control of the conversation. This can help you steer the conversation in a productive direction and ensure that your needs are being addressed.