My in-laws got a call from their "grandson" a few weeks ago. My MIL made the mistake of using my youngest DS' name so the caller used it. She said it sounded like him. He said he'd been in an accident and not to tell his parents (us) because they'd be angry or upset (can't remember) and he needed money to get out of jail. The call was from a different state than DS or us live in. First, DS is 28 and married and lives in a different state than us. The guy said he'd have his lawyer call them later which he did, but by then they'd talked to us and didn't give the guy any money. We made sure they understood that both our DS' would never call them like that and ask it to be kept a secret. Our sons would call and tell us because that's the relationship we have. Also, DS would have called his wife, us, his in-laws, or his brother long before calling MIL and FIL (or my parents). DH lectured them both about scam phone calls, including those from the IRS and they understand to not give any credit card info or send money orders to anyone without talking to us first.
We get so many phone calls that I don't answer because we have caller ID. I usually google them and 90% show up as known callers for everything from political calls to scams to info about anything and everything, all usually involve paying something.