Sahih Bukhari, Chapter: Wills and Testaments (Wasaya)

I heard Allah's Apostle (SAW) saying, "All of you are guardians and responsible for your charges: the Ruler (i.e. Imam) is a guardian and responsible for his subjects; and a man is a guardian of his family and is responsible for his charges; and a lady is a guardian in the house of her husband and is responsible for her charge; and a servant is a guardian of the property of his master and is responsible for his charge." I think he also said, "And a man is a guardian of the property of his father."