Is it permissible or forbidden for a father to favor his male child over his female child in gifts and endowments during his lifetime, on the grounds that a male receives the equivalent of the share of two females?

Scholars differ on the ruling concerning justice among children in gifts. The majority of scholars view it as recommended but not obligatory, while the Hanbalis consider it obligatory. They say that the male should be given double the share of the female, and this was also the view of Ata, Shuraih, Ishaq, and Muhammad ibn al-Hasan (definition). Abu Hanifa, Malik, Al-Shafi'i, and Ibn al-Mubarak hold the view that the female should be given the same as the male. Perhaps your father adopted the view of the Hanbalis, and there is no blame upon him for that.