The dower of his daughter or sister is one of her rights and it is a portion of her wealth. If she gives it as a gift to him or a part of it, voluntarily and out of free choice and she is someone legally capable of such an offer, then it is permissible for him to take it. If she does not give it as a gift, it is not allowed for him to take it or any portion of it as it is something that specifically belongs to her.
However, the father may take a portion of it, but only if such is not harmful to her and only if he does not take specifically from some of his children. This is based on the Prophet (sallallaahu ‘alaihi-wasallam) statement ,
''The best of what you consume is that which you have earned. And your children are part of what you have earned. ” 
 Recorded by al-Tirmidhi, and al-Nasai, and Al-Albani graded it Sahih Al-Albani, Sahih al-Jami , Vol.1, pg.326.