While we can't give medical advice we can help with information. I also freaked out when I saw that said about the nodes. I guess you can see why the medicos can get a bit antsy sometimes about us reading our own reports - nothing that a bit of explanation doesn't fix.
No question is too silly to ask - and sometimes someone else out there may have the same question.
Have you talked to your 7 year old about what is going on? How you deal with it is of course up to you but kids are often scared by "secrets" more than they are by knowing. As long as you keep the information age-appropriate. If you haven't done so, it's probably worth letting his/her teacher or someone else at the school know as well - it doesn't have to be public knowledge if you don't want it to be but it helps the school to deal with any anxieties that may present. My kids were older than yours when I was diagnosed (11, 12 & 15) - we've had some issues over the time but they know we don't hide anything about the cancer so they have been able to ask freely when they've been concerned. It doesn't mean I tell them the "what-ifs" but it helps for them to know that if I'm upset, it's okay.
