I would personally always demand proof of life regardless if fake or real and I would ask my family member to answer a question only they would know the answer

I would personally always demand proof of life regardless if fake or real and I would ask my family member to answer a question only they would know the answer to. We would of course have code words ahead of time. Maybe this is a sad anecdote, but the code phrase my mom and I had for duress was "I love you"