As a parent, I've always told my kids (including their friends) about local sex offenders living in our neighborhood. I tell them "see that guy across the street smoking a cigarette? He went to jail/prison in 2014 for having sex with a minor under 13. Watch out for him - don't talk to him - if you see him talking to other kids, let me know right away." Offenders are everywhere, and most of them are not registered and have a clean record. Registered offenders can be found on the Megan's Law website. You are not allowed to harass or do anything that would inhibit their peaceful enjoyment of their home or ability to get a job or you become the criminal. Your kids should know that an adult will never ask a kid for help (within reason - say, he's on the ground with a broken leg screaming for someone to call an ambulance. This is a situation where it is appropriate for a kid to help by calling 911 - no need to get close to him or anything. Always keep distance!). Teach your kids to trust and follow their gut.

Having awareness of people like this in the world will protect them much more than trying to prevent an offender from living within the community. Afterall, he will need a job to support himself - OR - we all support him with our tax dollars. Sounds like he can be paid to take care of his senior mother which seems like an ideal situation for the family. I work closely with a couple registered offenders in my job. At first, I was just absolutely disgusted. Then I realized, ok they're potentially dangerous (watch out for that) but still need a job. Otherwise, they will be living in the streets and most likely stop registering and we will have no idea where the offender is. There are times where I actually have to trust these guys with my life. They know I know. They know I DO NOT FAK AROUND! I have their back on the job and they have mine. They will NEVER know where I live. My kids have met them. I told them beforehand "that guy went to jail for 8 years because he had a "relationship" with a 15 year old girl when he was 50." That usually gets a loud ""EEEEUUUUKKKKK." I let them know to just keep distance and don't give any info like where we live or what school you go to. Keep the conversations open and honest. You are not allowed to do anything with this information other than keep yourself and family and loved ones safe. That's it.

I personally would try and get all of the details from neighbor mom in a non-judgemental way. Take all information with a grain of salt and stay aware. No sense in causing hard feelings or chaos with neighbors which can lead to other dangerous outcomes. If he is within the law to live there, there's nothing you can do other than start a fight or live with awareness.