Tips for meeting Bf's family?

I'm meeting my boyfriend of a month's family after his orchestra concert on Saturday (we're college students and this is just how our schedules are working out). This will include his parents, older brother, and sister in law. Tips for what to do/say? Would it be bad to bring a friend in case things got really awkward? What's worse is that our relationship is in an ambiguous place right now; we were just fwb for most of the last year but lately he's been pushing for more out of the relationship, hence meeting the parents. It's also bad timing because we're both going home soon (7 hrs apart).