The probenecid holds the ammox in the blood stream longer. And yes, it can be used in children above the age of 2:
www.drugs.com/cons/probenecid.html"Probenecid has been tested in children 2 to 14 years of age for use together with antibiotics. It has not been shown to cause different side effects or problems than it does in adults."
Astragalus is a good choice, but not just for treatment, for yearly protection as well! I live in Arkansas, and I stay on astragalus all year long to make sure that I never have to live through another infection. I've had enough of them.
IgG happens when the immune system is overwhelmed - which can take years, or weeks according to what I've read.
"Also, I know I am also worried about
the fact that possibly I had this when I had my kids. If that was the case, would he have made antibodies to more bands? "
Not necessarily - again, it all depends on the strength of the immune function. He could have been weighed down with most any other thing, and the Lyme got ahead of his immune function, so it can no longer make antibodies to it. That's fairly common in the adults that believe they have been ill for a while - and it happened to me.
Remember, the Lyme bacteria inhibits the immune function, so it can't make antibodies to the bacteria. That's why there was a campaign for a few years to "Treat the Bite" - as you can't be too careful with these infections. They are very hard to detect and the devastation to a person's life can be really bad.