I'm the oldest of 3 sisters and my youngest sister, C, age 20, has been dating a guy for a little over a year. Recently, my other sister, R, had a conversation with one of C's friends and through that conversation learned of two separate incidents (though we're not sure of the dates) where C's boyfriend had been physically aggressive with her in front of a group of people. (The first time he pushed her off of his lap and onto the ground in an attempt to quit her from showing PDA. The second time he told her to shut up and hit her in the face, "the way you would discipline a dog".)
Obviously, we have decided that we need to talk to C about this. Her friend told us that C and her boyfriend plan to get engaged in the next year or so and of course we want to address this as quickly as possible. Unfortunately, R and I aren't especially close with C these days - I live several states away and I've never actually met her boyfriend - and we're worried that she will immediately shut down and become angry when we bring up the subject. Can you offer any suggestions or resources on the best way to share our concern without alienating our sister?
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