Hi B.,
I'm not a doctor but I do know that there are lymph nodes in the base of your head above your neck (cervical lymph nodes). Lymph nodes are usually the first place you can notice an infection. That's when they swell and you see them, like a small pea sized knot. Sometimes you have no symptoms because the lymph nodes have contained it for the immune system to fight it off. If you can see them, I wouldn't worry but I would do something to boost her immune system so whatever it is, it will go away before there is a problem.
If you're unfamiliar with boosting the immune system in little ones, I'd be glad to give you more information.
Regards,
M.
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