6mo has 2 swollen lymph nodes on the back of head on left side for months. her pediatrician says not to worry. haven't changed in size. should i be co?

Usually is benign: Lymph nodes are located throughout the body & generally noticeable in exposed areas like the neck. They are usually pea sized at rest and enlarged when stimulated by bug bites, dermatitis, drainage or infection. They rarely can become damaged by infection & grow to golf ball size & need drainage or removal. Most enlarge and later shrink back down within a 3 wk cycle unless chronically stimulated