The bleeding disease is due to the deficiency of Vitamin K.
Vitamin K plays a major role in the process of blood clotting. It is involved in the posttranslational modification, and activation of the clotting factor II (prothrombin), VII, IX, and X in the liver.
The deficiency of vitamin K results in the lack of active prothrombin. Due to this blood clotting is adversely affected, and the clotting time is increased.