Answer
Princess Irina Alexandrovna was the niece of Tsar Nicholas II, the last emperor of Russia. Irina's father, Grand Duke Alexander Mikhailovich, was the younger brother of Nicholas' father, Emperor Alexander III. Princess Irina was thus first cousins with Nicholas' children, the Grand Duchesses Olga, Tatiana, Maria, and Anastasia, as well as Tsarevich Alexei.