Julia is explicitly identified as John's daughter.
At the end, John Bosload's daughter Julia arrives at his publishing office.
Julia's appearance clarifies that she is not the same person as Julie.
Julia arrives at John's office after Sarah leaves and is revealed to be a different person from the young woman who visited the French house.
The film distinguishes Julie from John's actual daughter Julia.
The ending explicitly reveals that the girl at John's office, Julia, is different from the girl who came to the country house.
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