All players are marked by their nails but pawns are marked by nothing more. They tell nothing and no-one thinks to look for them at first. Unless there's an older sibling or a close friend: someone to snatch their hand up and see and then explain -
But not all who see, explain. Some will take others' ignorance as their advantage.
She's lucky, then. She has no siblings, and no friends close enough to use her and then toss her into a ditch - or a chessboard. That doesn't save her from a match, but it saves her at least from betrayal.