Our daughter was born a few weeks ago. In her very first baby pictures (first few days or so), the mark in question was very, very light (about the same colour as the also-present "angel kisses" between/above her eyebrows. But, a few weeks later, the "angel kisses" have faded significantly and the larger mark in question is now much darker.
I have temporarily placed a photo here: http://www.karaokeyoga.com/possible_pws.jpg
This photo is about a week old and the mark is darker now. From what I've read, PWS are present at birth, but I'm wondering if anyone knows if they're very dark right at birth?
We live in San Francisco and plan to see a specialist when we get back in two weeks, but are currently in Japan (where our daughter was born). Seeking information in advance.