Simplify the following text for a Grade 7 native English-speaking person.
Original: She was an elder sister of the famous Grand Duchess Anastasia Nikolaevna of Russia , whose alleged escape from the assassination of the imperial family was rumored for nearly 90 years .
Simplified: She was an older sister of Grand Duchess Anastasia Nikolaevna of Russia . Her sister Anastasia was famous for stories about her escape from the murder of the royal family for almost 90 years .