Board Thread:General Discussion/@comment-67.248.240.148-20170908201845/@comment-26397825-20180320023951

Summer was the leader of STRQ; in the beginning of V3 Ruby is talking to her gravestone and mentions that she is the leader of Team RWBY, "Like mother like daughter". There's also the fact that the leader's name is always the first initial of the team name, and STRQ starts with an S, not an R.

And we don't know who killed Summer, but so far it has been implied that she was killed by Salem's lot. When they talk about the Silver Eyed People in early V4, Hazel asks why Cinder had so much trouble with a novice when 'they've dealt with their kind before'.