I pretty well agree with what's been written above. The only twist I would add is this; keep an eye out for a thaw in someone's attitudes. Surely, somebody in your family is not quite as anti-gun as the group dynamics have probably caused them to believe they are. If or when you sense somebody's curiosity about shooting, encourage them! Offer to take them shooting. Show them a good time. Like mentioned earlier, you won't be able to out argue them into changing their minds, but your example may trigger a change in their attitudes (pun intended).