Proposal..

So me and my boyfriend are in a LDR. we have talked about when we want to get married and when we can finally start living together. we picked December of this year! But now all he has to do is propose! But, problem is he wants to propose but doesn't want to be engaged? meaning that he doesn't want to tell our family we are engaged.. I don't know how to feel about that because I am close to my family and it's an exciting, happy thing ! But he says he doesn't want them to know because he knows they would be worried.. What would you guys do in this situation ?..