In this task you will be given an answer to a question. You need to generate a question. The answer given should be a correct answer for the generated question.

Let me give you an example: This list contains the top 25 accounts with the most followers on the social photo-sharing platform Instagram. As of May 2018, the most followed user is Instagram's own account, with over 235 million followers. Selena Gomez is the most followed individual, with over 137 million followers. Ten accounts have exceeded 100 million followers on the site.
The answer to this example can be: who has the maximum number of followers on instagram
Here is why: The answer is talking about the Instagram accounts that have the most followers. The question asking about the maximum number of followers. So this is a good example.

OK. solve this:
Hilary Erhard Duff (born September 28, 1987) is an American actress, singer, songwriter, businesswoman, and author. Duff began her acting career at a young age and quickly became labeled a teen idol as the title character of the Disney Channel television series Lizzie McGuire (2001 -- 2004) and in the theatrical film based off the series, The Lizzie McGuire Movie (2003). Thereafter, Duff appeared in numerous films, with leading roles in Agent Cody Banks (2003), Cheaper by the Dozen (2003), A Cinderella Story (2004), and Cheaper by the Dozen 2 (2005). After experiencing commercial and critical failure in Material Girls (2006), Duff began appearing in independent films such as War, Inc. (2008), According to Greta (2009), and Bloodworth (2010). Since 2015, she has starred as Kelsey Peters on the TV Land comedy-drama series Younger, for which she has received nominations for People's Choice Awards in 2016 and 2017.
Answer:
how old was hilary duff a cinderella story