FRENCH GIRL 
So, I struggled to find any French actresses at the age you were looking for, so I decided to use some who, while is older, could still be believable to be younger and the daughter of Marion (in some of them). Not all of them have blue eyes. Not all of them are French, but have small amounts of French in their ethnicity.
[ REQUESTED; belasuper45 ]

ADELE EXARCHOPOULOS (24)
Greek, French

ADELE HAENEL (29)
French

STACY MARTIN (27)
French, English

MELISSA BENOIST (29)
German, English, Scottish, French

CARA DELEVINGNE (25)
English, Welsh, Ashkenazi Jewish, Dutch, German, French, Scottish, Irish, Jersey (Channel Islander), Portuguese