Is it permissible to take money from the father without his knowledge, from funds designated for his daughter's trousseau, and spend it on other things, given the father's awareness and affluence, and his prior refusal to do so?

The basic principle is the inviolability of a Muslim's property unless it is given willingly by him. This is further emphasized in the case of a father, because taking from his property without his consent may lead to disobedience (Uqooq al-Walidain), which is one of the gravest sins. If the father is already providing for his daughter's sustenance, it is not permissible for her to take from his money without his permission for what she referred to as "other needs." The bridal trousseau is not an obligation upon the father. The matter remains that it is impermissible to dispose of his property except with his consent. She can request what she needs from him or seek the help of someone influential with him.