User blog comment:Percy Jackson12/The Seven/@comment-4490610-20111016043520/@comment-3146930-20111016044430

Considering that out of the six we know, 5 are completely knew characters it wouldnt surprise me if they met a child of Athena/Minerva in Rome or Rick uses a Rachel Elizabeth Dare type character (a character that has a small part when first introduced, but becomes more important later) that turns out to be a child of Athena/Minerva in Book 4