We still don't know what is wrong exactly.
It is gradually fading in the order it came out, so her cheeks are now normal colour, the bottom of the bib is still bright, but her neck is normal... her cheeks look puffy today but I think that is where it came out on her chin a day or so later so she has a red patchy chin, but normal cheeks.
She is whingey, sick of being at home, but other than that, just looks bloody odd.
It doesn't fit anything I googled now it is dying off.
Really odd.
MumofMonsters says her son had similar a while back though - they called it Slapped Fever