Per general etiquette, the mother of the bride buys her wedding day outfit first, then notifies the mother of the groom about the color, length and overall formality of her choice. But if the groom's mom doesn't get word by the four-month mark, she should touch base with the bride-to-be about what to do.
Genetics. The two main types of hemophilia are caused by gene mutations that affect the levels of clotting factors in the blood. Mutation of the FVIII gene leads to hemophilia A, also called classic hemophilia, while a mutations in the FIX gene leads to hemophilia B, also called Christmas disease.
Haemophilia B (or hemophilia B) is a blood clotting disorder caused by a mutation of the factor IX gene, leading to a deficiency of factor IX. It is the second-most common form of haemophilia, rarer than haemophilia A. Haemophilia B was first recognized as a different kind of haemophilia in 1952. It is sometimes called Christmas disease, named after Stephen Christmas, the first patient described with this disease.