Q: In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. 
 Avoid questions that can be answered correctly without actually understanding the paragraph. Avoid questions that do not link phrases referring to the same entity. Avoid questions that have multiple answers. 

 For each of your questions the answer should be one or more phrases in the paragraph. The answer for each question should be unambiguous. 
Context: According to Italian fashion designer Roberto Cavalli, Beyoncé uses different fashion styles to work with her music while performing. Her mother co-wrote a book, published in 2002, titled Destiny's Style an account of how fashion had an impact on the trio's success. The B'Day Anthology Video Album showed many instances of fashion-oriented footage, depicting classic to contemporary wardrobe styles. In 2007, Beyoncé was featured on the cover of the Sports Illustrated Swimsuit Issue, becoming the second African American woman after Tyra Banks, and People magazine recognized Beyoncé as the best-dressed celebrity.
A:
Which parent of Beyonce's help co-write a book?