The last of Queen Victoria's daughters, Princess Beatrice was also a carrier. She married Prince Henry of Battenberg and had three sons and one daughter. Her eldest son, Alexander, was healthy; the second one, Leopold was haemophiliac and died young and unmarried. There is some doubt about the third one, Maurice, of beeing haemophiliac or not; some authors say he was others say he was not. Nevertheless he died young and unmarried, being on active service on World War I. In my own opinion, I think that an haemophiliac shouldn't had been allowed to go to war, so it is more probably that Maurice had died of war wounds and not for being haemophiliac.
Beatrice's only daughter, Victoria Eugenia, married King Alfonso XIII of Spain. She was a carrier so she introduced the haemophilia's gene into the Spanish Royal Family. Two of her sons, Alfonso, heir to the throne, and Gonzalo had the disease. This fact damaged Victoria Eugenia's relation with her husband and weakened the position of monarchy in Spain. Antibritish circles claimed that the genetically defetive British Queen had defiled the blue blood of Spanish Royalty. Many Spaniards believed the story that each day a young soldier was sacrificed in order to keep with his fresh blood, the haemophiliac sons of the King alive. In fact, the haemophiliac gene transmitted by Victoria Eugenia to her sons discredited her marriage and the liberal democratic fashion who favoured it and was one of the factors that lead Spain to Civil War. The two other sons of Victoria Eugenia, Jaime and Juan (father of the actual King Juan Carlos), were free of the disease. Her two daughters were apparently not carriers, since there hasn't yet appear any haemophiliac in their families, but there is still a chance that the fatal gene appears again in any of their descendants.
Henry of Battenberg XY
Beatrice Xx
Victoria Eugenie Xx
Maurice
xY ?
Leopold
xY
Alexander XY
Alfonso XIII
XY
Jaime XY
Gonzalo xY
Alfonso xY
Beatriz XX
Cristina XX
Juan XY
But which was the origin of the haemophilia gene on Queen Victoria's genetic code ?
Here are some theories;
1) It could have occured a mutation at the moment of the Queen's conception in the genetic code of her father, the Duke of Kent, who was an old man (this is the most accepted theory).
2) Queen Victoria was not the Duke of Kent's daughter. Her mother had a supposed haemophiliac lover who was the real father of the Queen.. This theory is exponed by Potts in his book "Queen Victoria's gene".
3) In the female line of Queen Victoria's family tree, there are many women whose sons died in childhood. There is not registered any case of haemophilia, but it is possible that any of these boys had suffered. There is indeed one adult that could have been a potencial sufferer: Heinrich LI of Reuss Ebersdorft, who was a brother of Queen Victoria's maternal grandmother, Augusta of Reuss Edersdorf. Heinrich LI died in a convulsive fit, just as the haemophiliac son of Victoria, Prince Leopold. If he had indeed haemophilia, her daughters would have been carriers, and one of them had five sons, four of whom died in childhood; two of them are said to died of apoplexy. This is not a proof but it suggests that haemophilia could have been in the Queen's maternal family before she was born. There is another interstig case: Queen Victoria's half sister Feodora (daughter of the Duchess of Kent's fist marriage), who could have also been a carrier, had two daughters; both of them had sons who died in childhood. Author Charlotte Zeepvat presents this interesting theory in her book about Prince Leopold.
Heinrich XXIV of Reuss Ebersdorf
Karoline of Erbach Schoenberg
(Potential carrier)
Augusta of Reuss Ebersdorf (Potential Carrier)
Franz of Saxe Coburg Saalfeld
Heinrich LI of Reuss Ebersdorf (died of convulsive fit)
Victoria of Saxe Coburg Saalfeld (potential carrier
Adelheid (Potential carrier)
Queen Victoria
(Carrier)
Feodora (Potential carrier)
Heinrich XI
1828-1830
convulsions
Heinrich V
1821-1834
apoplexy
Heinrich XVI
1835-1836
apoplexy
Adelheid (Potential carrier)
Feodora (Potential carrier)
Viktor
14-17 May
1865
Friedrich
1857-1858
Augusta Viktoria (Kaiser Wilhelm II's wife)
Gerhard
Jan-April 1862