This exchange shows Philip clearly defying the advice of his godfather and legal guardian. However, it is important to notice that Nick Kendall blames Rachel not only for overdrafting her account, but also for (possibly) sending the money out of England. Du Maurier seems to be subtly pointing out how men inexorably try to control women; even though the money in Rachel’s account is legally hers, she is not allowed to do with it what she wishes without scrutiny from male characters like Kendall.