Melissa grew up in Sayville, New York. Her acting career started at the age of four when she did a commercial for a bathtub toy called "Splashy". Her mother, Paula Hart, has been her agent from the beginning. Melissa has five younger sisters, Trisha Hart, Elizabeth Hart, Emily Hart, Alexandra Hart-Gilliams and Samantha Hart, two younger brothers, Brian Hart, and Mackenzie Hart.

Elizabeth Hart, Emily Hart, Alexandra Hart-Gilliams, Samantha Hart and Brian Hart have appeared on Melissa's current TV series, Sabrina, the Teenage Witch.

Melissa performed in two plays as the youngest member of New York's Circle Repertory Lab Company: "Beside Herself" in 1989 (starring Lois Smith and William Hurt) and "Imagining Brad" in 1990. She was also in the National Actors Theatre production of "The Crucible" on Broadway with Martin Sheen (as understudy to three of the children in the play). Melissa cites Shirley Temple and Audrey Hepburn as early acting inspirations. She still collects Shirley Temple memorabilia. For the past few years, she has been juggling acting and attending New York University. She's now living in the Los Angeles area, starring in the ABC-TV series Sabrina, the Teenage Witch, which is produced by Hartbreak Films, the production company run by her and her mother.
Daughter of Paula Hart and William Hart, a lobster wholesaler. Met longtime boyfriend, actor James Fields, while filming an episode of Touched by an Angel in Utah. Sister of Trisha Hart, Elizabeth Hart, Brian Hart, Emily Hart, half-sister of Alexandra Hart-Gilliams and Samantha Hart. Has sung on two rock/pop albums, "This Is What 'NA NA' Means" (1994) and "Sabrina, the Teenage Witch: The Album" (1998), and narrated a classical album for children, "Peter and the Wolf" (1994). Performed in off-Broadway play "Beside Herself" with William Hurt and Calista Flockhart in 1989. Small role in 'Crocodile' Dundee was cut from the film. Appeared in underwear along with Yasmine Bleeth, Alyssa Milano, Peta Wilson, Garcelle Beauvais, Carmen Electra, Jamie Luner, and Jeri Ryan on the cover of and inside the October 1997 issue of "Details" magazine. Was born at 1:30 p.m. on Easter Sunday. Has a "lazy eyelid" that causes her right eye not to open as wide as her left. Was born without the teeth to either side of her two front teeth, a condition that was "fixed" in 1993. Is vice-president of Hartbreak Films, a production company she runs with her mother, Paula Hart, and step-father, Leslie Gilliams. Collects Shirley Temple and Audrey Hepburn memorabilia. Auditioned for the title role in Adrian Lyne's Lolita. Full name is Melissa Joan Catherine Hart: "Melissa" from the The Allman Brothers Band song, "Joan" from her maternal grandmother, "Catherine" is the name she chose herself as her confirmation name. Can recite pi to 341 digits Hobby: collects great paintings; owns 3 Picassos Started collecting estate jewelry. [October 1999] Her sister, Emily Hart, provides the voice for Sabrina in the Saturday morning cartoon Sabrina the Animated Series, which was spun off from Melissa's hit show Sabrina, the Teenage Witch. Melissa provides the voices for Aunts Hilda and Zelda Spellman. Has attended New York University via correspondence courses since January 1994. She is pursuing a BA in a combination of art and literature classes, but put her studies on hold for 1 year due to her hectic filming schedules. [October 1999] Auditioned for a role in Eyes Wide Shut. Auditioned for the role of Sidney Prescott in Scream . The role eventually went to Neve Campbell. Announced engagement to Mark Wilkerson, front man/guitarist for "Course of Nature". [January 2003] She and her husband, Mark Wilkerson, are the proud parents of two sons, Mason Walter Wilkerson born on January 11, 2006 weighing 9lbs exactly and Braydon "Brady" Hart Wilkerson born on March 12, 2008 weighing 7lbs 3oz. Her wedding was themed with the colors Purple and Gold, which also happen to be the colors of Sayville High School, her alma mater. Turned down the role in I Know What You Did Last Summer that eventually went to Sarah Michelle Gellar and also a part in Urban Legend and, in a later statement, expressed reservations of becoming another horror movie victim as the rationale behind her decisions. Has three dogs: Pele, Halleakala and Cooper. Stepdaughter of Lisa Hart. Sister-in-law of Warren. Aunt of Chris and Jonny. Granddaughter of Joan. Older half-sister of Mackenzie Hart born on December 29, 1997. Attended Sayville Middle School till 8th grade and then moved to New York to concentrate on Clarissa Explains It All. Hobbies: snowboarding, hockey and watching TV (esp. basketball), movies, guitar, flute and painting. Her parents divorced in 1991. Mother married Leslie Gilliams in 1994. Granddaughter of Ethel Hart. Childhood friend of Soleil Moon Frye.