Is it permissible to secretly send charity to a female relative without her husband's knowledge?

A woman is permitted to own money without her husband's permission or knowledge, as her financial independence is established. Regarding giving her charity, it is permissible in cases where she or her husband is poor, or if her husband is wealthy but withholds her right to maintenance. In such situations, it is permissible to give her zakat and voluntary charity. However, if she is wealthy from her own money or her husband's money, it is not permissible to give her obligatory charity (zakat), though voluntary charity may be given to her. It is preferable that a woman similar to her handles the payment, and if that is not feasible, a man may give it to her, provided there is no suspicion, doubt, or impermissible Sharia acts involved.