My boyfriend of four years proposed yesterday morning (!) and of course we were super excited to tell our family. Naturally, since he proposed at 7 AM, we had to wait. We both agreed to call our respective families around noon or so. I did, but I didn't realize that he didn't (he got caught up at work and didn't have the time, as I found out later).He called his parents that night, around 8 PM (when his dad gets off work) and thought that his brother and sister-in-law would be sleeping, so he made plans to call them today instead.Here's the thing: I posted on Facebook that afternoon that we were engaged, and his sister-in-law saw it before my fiance had a chance to call. So she called my fiance's mom and told her what she saw on Facebook (thankfully, after we had told his parents), and was upset that not only had we not called, but we hadn't asked the brother to be the best man yet (as my fiance was for him when he got married). I think she should calm down and that it's not as big a deal as she's making it out to be.My fiance thinks that I shouldn't have said anything on Facebook until we had told everyone (in my defense, I thought that he had). I think the sister-in-law is overreacting (the brothers are not very close). My fiance thinks I'm underreacting, because it's "family". So now I'm confused and upset and I don't know what to do and I've only been engaged a day.