According to the old Russian calendar (otherwise known as the Julian calendar), Alexei Nicholaevich Romanov was born on this day in 1904. The youngest of the Romanov children, Alexei was the heir apparent to the throne of the Russian Empire. This meant that he was known as the tsarevich or tsesarevich in accordance with the logic behind Russian royal titles.
Alexei famously suffered from hemophilia, a disease which prevented his blood from clotting properly in the event of a wound. This also made the risk for internal bleeding greater. Because of this desease, the gene of which had been passed from his mother, Alexei's life was not the life of a normal young boy. He had to be constantly supervised, was often in pain or ill, and often had to be carried. Doted on by his mother the Empress, Alexandra Fyodorovna, Alexei was the source of much concern and worry.
Alexei Romanov was killed in 1918, before his 14th birthday, along with his family at the Ipatiev House in Ekaterinburg. While there are plenty of stories about how Alexei survived the "attempt" on his life, Alexei most certainly perished that night. While accounts tell of bullets deflected by jewels sewn into the Romanovs' clothing, even a small injury would have been fatal to Alexei, especially without a doctor's care.
Books about the tsarevich's survival are meant to be convincing, and should be looked upon as novelties rather than evidence that Alexei lived beyond the year 1918. While the most noise has been made about Anna Anderson as Anastasia, if all "proof" was to be believed, the entire Romanov family would have walked out of the Ipatiev House alive.