Praise be to Allah.
This hadeeth includes both sons and daughters. This is also indicated by the hadeeth of ‘Aa’ishah (may Allaah be pleased with her) in which the Prophet (peace and blessings of Allaah be upon him) said: “The best of that which you consume is that which you earn, and your children are part of that which you earn.” Narrated by the five. But that is subject to the condition that this does not cause any harm to the child, whether male or female, because the Prophet (peace and blessings of Allaah be upon him) said: “there should be neither harming nor reciprocating harm.” And there is other evidence which says the same thing. And the father should not take for the purpose of accumulation, rather he should just take what he needs.
May Allaah send blessings and peace upon our Prophet Muhammad and his family and companions.