What permitted the Hanbalis to make an endowment for some descendants to the exclusion of others, and what are their proofs?

Specifying males for endowment (waqf) to the exclusion of females, or vice versa, is permissible according to the Hanbalis if it is due to a need or a merit, and disliked if it is out of favoritism. They (the Hanbalis) also consider it desirable to be just among children in endowment, with the male receiving a share equal to that of two females. Sheikh Ibn Uthaymeen, however, favored the invalidity of an endowment designated for some children to the exclusion of others, as it is considered an injustice. Other madhhabs (schools of thought) validate the endowment, albeit with dislike, if there was no intention to cause harm. The correct view is the obligation of justice in the division among children, both males and females.