1. Reese Witherspoon
By the time Reese Witherspoon was 25, she had already been in a ton of different movies, including Pleasantville, Cruel Intentions, and Election. In fact, the forever-iconic Legally Blonde came out in 2001, which is the same year she turned 25. Talk about being an accomplished actress. 

Reese also married and had children young. She married Ryan Phillippe in June 1999, and gave birth to their first daughter, Ava, in September of that same year. Their son was born in October 2006, and her son with current husband Jim Toth was born in September 2012.