Simplify the following text for a Grade 11 native English-speaking person.
Original: Anastasia 's older sister , Maria , reportedly hemorrhaged in December 1914 during an operation to remove her tonsils , according to her paternal aunt Grand Duchess Olga Alexandrovna of Russia , who was interviewed later in her life .
Simplified: Anastasia 's older sister , Maria , is said to have hemorrhaged in December 1914 during an operation to remove her tonsils .