person A: I recently had a big argument with my sister. We both got very upset and angry at each other.
person B: Isn't that what sisters are for?  What were you guys upset about?
person A: I'm not so sure. We just had a discussion that heated and became an argument with tempers flying.
person B: Maybe once you feel like you can bring it up again_comma_ you can try to approach the topic from another angle.