During World War I, which nation's monarchs were blood related?

During World War I, the monarchs of England, Germany, and Russia were blood-related through Queen Victoria, who held the title of Empress of India as well as being the monarch of the United Kingdom. Queen Victoria was the grandmother of Kaiser Wilhelm II of Germany, and Tsar Nicholas II of Russia. Thus, a family connection existed between these three nations, as they were all descendants of Victoria, which made the conflict even more complex and personal.