First, I offer you some reassurance. If she is already attending a French language kindergarten, she will pick up a good bit of the language. The younger the child, the easier that seems to be. Talk to her current teacher about it and ask her for suggestions of books you can provide, summer activities, etc.
Since you work full-time, I assume your daughter will be in some type of child care over the summer. If possible, I would try to find one in which French is the major language. If you use in-home care, try to hire a French-speaking nanny. And arrange as many social events for her as you can with French-speaking children—having them over to your house, taking one or two with you on shopping excursions, etc. Weekly excursions to the library to check out books in French will also help.
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