Small bumps

So I noticed a small skin colorish bump on my daughters back when she was about 10 months old. I didn’t think much of it because it didn’t seem to irritate her or bother her in the least bit. I thought it may just be a skin tag. Well now she’s a year and and half and has about 11 more all in a small cluster and she doesn’t have them anywhere else. They still don’t bother her, I don’t even think she knows they’re there. I mentioned it to her doctor at her 1 year check up when there was only one with another one forming. She basically just said babies skin does weird stuff sometimes but I shouldn’t worry. But now that they’ve multiplied so much I’m a bit concerned. So I guess I was just wondering if anyone else has experienced this?