Lakin was born in Dallas, Texas, the daughter of Karen (née Niedwick) and James Daley Lakin, and raised in Roswell, Georgia. She graduated from The Lovett School in 1997.[citation needed] She graduated from UCLA with a B.A. in Communications.

Christine Lakin got her start acting in commercials, before landing her first major role as Young Rose in the American Civil War drama The Rose and the Jackal. That movie aired in 1990, one year before she was cast as Al Lambert, the tomboyish daughter, on Step by Step.

After Step by Step was cancelled in 1998, she continued to appear in television movies, such as Showtime's Reefer Madness and 2005's Who's Your Daddy?.

In 2006 she was a regular cast member in MTV's Wild 'n Out, an improv comedy show similar in structure to Whose Line Is It Anyway? She also appeared in commercial called "But He Has Bud Light" that aired during Super Bowl XLI, in which her male companion wants to pick up a hitchhiker who has Bud Light beer in one hand and an axe in the other.

In 2008 she starred alongside Paris Hilton in the movie The Hottie and the Nottie, requiring extensive makeup to make her appear ugly. The film met dismal reviews in the US. As of 2008, she also has several new films in either production or post-production.

In 2010 she became Craig Kilborn's sidekick (his "Huckleberry Friend" - a reference to his "favorite movie", Breakfast At Tiffany's) on "The Kilborn File" on select Fox stations.

She was nominated in 1993 for a Young Artist Award for Best Young Actress Starring in a Television Series and in 1994 for another Young Artist Award for Outstanding Youth Ensemble in a Television Series shared with Josh Byrne, Christopher Castile, Brandon Call, Staci Keanan and Angela Watson - both for Step by Step (1991). She also won a Golden Raspberry Award for Worst Screen Couple with Paris Hilton in The Hottie and the Nottie.