Is zakat obligatory on all saved money, whether it be from the father's money or one's personal money, or only on one's personal money, and what about the past years for which zakat was not paid?

What a father saves for his daughter becomes her property from the moment it is saved if it is a bestowal of ownership and not a bequest. Zakat is obligatory on it if it reaches the nisab and a year has passed, even if the father did not pay the zakat. The daughter must pay it for the past years, and she should strive to estimate the duration and amount if that is difficult for her.

If she delays the zakat without excuse, she has sinned, and she must pay it for all the delayed years. She should act upon her best judgment in estimation if she is in doubt.

The same ruling applies to what the daughter has saved from her salary. Zakat can be paid from money other than the saved money, but if it is not sufficient, then it must be paid from the saved money. However, if what the father saved was a bequest or conditional upon reaching maturity, then it has a different ruling that requires elaboration.