That scam is common everywhere and I think before they attack a target, they're knowing first details of the victim that they're going to copy. That's why they're also observant before doing the scam and you don't display all your sensitive information on the web or any social media platform.

Talk to your family that you should have a sign or words to say that you're actually legit the ones talking to them and vice versa. If that word isn't mentioned by the caller then that means it's not you that's calling them for help. Start to do this in circle of your family and have yourselves call sign that you and them only know it, don't tell it publicly because the scammer might know what you're up to and will also copy that call sign of yours or anything that's going to be unique and you can identify each of yourselves easily.