history: I recently got very upset with my sister when said some very mean things to me. I let her know that she was out of line by yelling at her. I feel bad for both of us. I recently had a big argument with my sister. We both got very upset and angry at each other. Isn't that what sisters are for?  What were you guys upset about?
current: I'm not so sure. We just had a discussion that heated and became an argument with tempers flying.
next: Maybe once you feel like you can bring it up again, you can try to approach the topic from another angle.