I totally agree that you shouldn't ignore it. I don't trust collection agencies or reporting agencies not to put a bogus report out there with anyone or anything that has a social security number -- and kids get those at birth now.
Definitely contact them and let them know that they are trying to collect a debt from a 4-year-old. Then file a complaint as Debra suggested.
Boomer, In response to the part of your original question about the collection agency waiting so long to try to collect on the past service, they probably just took custody of the bill from the service provider. Many years ago I had a pre-employment physical with my own physician. The bill was to be sent to my new employer for payment. Five years later I received a letter from a collection agency for nonpayment. I recognized the date and knew immediately what it was for. I called the drs office and was told that they'd had problems with their office staff and had recently discovered a number of invoices that had never been sent. Rather than deal with the invoices, they sent the whole pile to a collection agency. I was furious that my name had been turned over to a collection agency for a bill I never expected to receive.
Chances are the collection agency tracked you down from Mo's legal records. Any bills he incurred before he came to you are the responsibility of his guardian at the time (biomom). I agree with those who say you should contact the agency and let them know that you are not responsible for this bill. You can give them biomom's address, or not, as you choose.
