Melissa Ellen Gilbert (born May 8, 1964) is an American actress. Gilbert began her career as a child actress in the late 1960s, appearing in numerous commercials and guest-starring roles on television. From 1974 to 1983, she starred as Laura Ingalls Wilder, the second-oldest daughter of Charles Ingalls (played by Michael Landon) on the NBC series Little House on the Prairie. During the run of Little House, Gilbert appeared in several television films, including The Diary of Anne Frank (1980) and The Miracle Worker (1979). As an adult, she continued her career mainly in television films. From 2009 to 2010, Gilbert appeared as Caroline "Ma" Ingalls in the touring production of Little House on the Prairie, the Musical. In 2012, she was a contestant on season fourteen of the reality dance competition show Dancing with the Stars on ABC.

Gilbert served as president of the Screen Actors Guild (SAG) from 2001 to 2005. She briefly ran for the U.S. Congress in 2016, but withdrew her candidacy before the election. She is the author of several memoirs, a children's book, and a cookbook.

Gilbert was born in Los Angeles, California, on May 8, 1964, to a newly engaged couple, Kathy Wood, an exotic dancer, and David Darlington, a stock car racer and mechanic. She was placed for adoption immediately after birth. She was adopted the next day by actor and comedian Paul Gilbert and his wife, dancer and actress Barbara Crane, the daughter of The Honeymooners creator Harry Crane.

Gilbert was raised in her mother's Jewish religion. The Gilberts later adopted a son, Jonathan, who co-starred on Little House on the Prairie.

Gilbert's parents divorced when she was 6 years old. Her mother then married attorney Harold Abeles, and together they had daughter Sara Rebecca Abeles (the actress known professionally as Sara Gilbert) in 1975. In 1976, Paul Gilbert died. Although 11-year-old Melissa was told that he had suffered a stroke, she found out years later that he had been a VA patient who dealt with chronic pain, and that he had taken his own life. The marriage of Barbara and Harold Abeles later ended in divorce.

When Gilbert introduced herself to her biological father for the first time, her biological mother had already passed, but he said "You're Laura, aren't you? I knew it.’" Her siblings also recognized the similarity while watching the show teased him about it.

Gilbert's earliest television appearances were in dozens of commercials, including one for Alpo dog food with Lorne Greene (Michael Landon's television father on Bonanza). She also attended school with Landon's daughter, Leslie Landon. It was Leslie who informed her that she had won the role of Laura Ingalls Wilder, the second oldest daughter, on Little House on the Prairie, beating out over 500 child actresses for the part. The pilot was shot in 1973 and was a ratings success. Almost a year later, Gilbert began filming the series. During the show's run, Gilbert appeared in several television films, including The Diary of Anne Frank and The Miracle Worker.

Gilbert became close to the Landon family after her adoptive father died. However, a rift developed between Michael Landon and Gilbert after the revelation of Landon's affair with Little House's young makeup artist, Cindy Clerico. Gilbert had limited contact with Landon after Little House ended during the 1983–84 season. Seven years later, following his May 9, 1991, appearance on The Tonight Show Starring Johnny Carson where he discussed his pancreatic cancer, she was contacted by Landon's family and visited him at his Malibu home. Landon died one week later. When Gilbert gave birth to her son with second husband Bruce Boxleitner on October 6, 1995, they named him Michael, in honor of Landon.