Our daughter's NOA arrived a few days after the rest of us so I'm sure there's nothing to worry about.
Also, just in case you made the same error as me, we only filled in one I-485 (for my wife as winner). The rest of our family were listed on that form and I hadn't clicked that we needed an I-485 each. We did send in all the supporting documentation for the whole family. It was only when she receive her NOA and we didn't, combined with help from this form, that we realised. Once we sent our I-485's the rest of the NOA's came through.