Aug. 26, 2011— -- intro: Melissa Gilbert, who famously played Laura Ingalls on that quaint family drama "Little House on the Prairie," is dealing with her own real-life family drama.
Gilbert, 47, filed for divorce from Bruce Boxleitner, 61, moving to end their 16-year marriage five months after they announced their separation, according to The Associated Press.
The petition filed earlier this week cited "irreconcilable differences" as the reason. Gilbert is also seeking joint custody of their 15-year-old son, Michael Boxleitner, named after Gilbert's "Little House" creator and star Michael Landon, who played her father.
"We have loved each other for a very long time," Gilbert said in March, "and we share four incredible sons together."
In addition to Michael, Boxleitner and Gilbert have one son, Dakota, from her previous marriage to actor Bo Brinkman, and two other sons, Sam and Lee, from Boxleitner's first marriage to actress Kathryn Ogilvy.
Gilbert's sister, "The Talk" co-host Sara Gilbert, 36, has also split from her partner of 10 years, Allison Adler, 44, according to People. They will share joint custody of their two children, Levi and Sawyer.
A former president of the Screen Actors' Guild, Melissa Gilbert grew up in a Hollywood family. After starring in dozens of television commercials, she landed the role of Laura Ingalls on "Little House" at age 8. Michael Landon became a surrogate dad to her when her own father died.
By her late teens, Gilbert rebelled against her perfect prairie girl image. She describes her battles with drug and alcohol abuse and co-dependence on men in her 2009 memoir "Prairie Tale."
Gilbert, who was once engaged to Rob Lowe, also dated John Cusack, Billy Idol and Tom Cruise.
Known as the "Queen of television movies and mini-series," Gilbert has starred in over 45 of them since the mid-'70s. She can also be seen touting hair care products on late-night infomercials.
Here's what's become of her former "Prairie" co-stars since the show ended.
quicklist: 1category: title: Alison Arngrim/Nellie Olesonurl: text:
Laura Ingalls and her nemesis Nellie Oleson may have scrapped on screen, but off camera Alison Arngrim, who played Nellie, was best friends with Gilbert.
"I had an intense, wonderful friendship with Melissa, who became a sister to me," Arngrim, now 49, told ABCNews.com last year..
Arngrim, who played Nellie during the series' original seven-year run, still gets e-mails from "Prairie" fans who say the show became their substitute family during their "horrible childhoods."
"Well, it was the same for me," she said.
In her recent book, "Confessions Of A Prairie Bitch: How I Survived Nellie Oleson And Learned To Love Being Hated," Arngrim revealed how she was sexually abused as a child, and how the role of bad girl Nellie helped her to heal. She also shared behind-the-scenes tales of one of the world's most beloved series.
Arngrim wrote that she was abused by a family member for nearly three years starting at age 6. The abuse made her, an already diminutive girl, even more shy and withdrawn.
That changed when Arngrim got the part of scheming brat Nellie Oleson at age 11.
"People were suddenly intimidated by me," Anrgrim said.
Other times, she was reviled like her character. Since age 11, Angrim has been called "bitch." She's been spat on, pelted with garbage and beaten up.
But thanks to Nellie, Arngrim found an outlet for the rage that had been building since her abuse -- a secret she kept from her parents until her twenties.
"When you're sexually abused you have a lot of anger," she said. "Usually victims turn the pain and rage on themselves. So to have an outlet where one could express this anger outwardly and openly was a fantastic opportunity."
Arngrim is grateful for Nellie. "Instead of her ruining my life, she gave me my life."
Coming from a show business family -- her father, Thor Arngrim, managed Liberace and her mother, Norma Macmillan, provided the voice for Casper the Friendly Ghost and Gumby -- Arngrim got to experience "normal family life" on the "Little House" set.
quicklist: 2category: title: Michael Landon/Charles Ingallsurl: text:
Michael Landon, who played Charles "Pa" Ingalls and produced the series, was very much the set's father figure.
"He saw to it that the rules were obeyed," Arngrim said. "We said 'yes, sir' and 'yes, ma'am.' We had to know our lines. We were held to a higher standard."
At the same time, Landon was nothing like the prairie dad he played.
"He was divorced and married several times," Arngrim said. "He lived in Bel Air and Malibu, attended the Playboy Jazz Festival, drove a Ferrari, smoked and drank. He had this wild sense of humor on set that really shocked people."
For one thing, he had an "unsaintly" habit of showing up without underwear on the set.
Landon was a fixture on the small screen. In 28 years, he starred in three successful television series: "Bonanza" in the '60s and early '70s, "Little House" in the '70s and early '80s, and "Highway to Heaven" in the '80s.
He married three times and was father to nine children and stepchildren. In April 1991, he was diagnosed with an inoperable form of pancreatic cancer. Appearing on "The Tonight Show" with Johnny Carson, he asked his fans to pray for him.
He died July 1, 1991 at age 54.
quicklist: 3category: title: Melissa Sue Anderson/Mary Ingallsurl: text:
Melissa Sue Anderson, who played Gilbert's on-screen sister Mary, wanted nothing to do with Gilbert and Arngrim.
"Melissa and I were wild and fun loving," Arngrim said. "Melissa Sue just looked at us and shook her head."
Anderson won the role of Mary at age 11 after appearing in several television commercials and guest starring on "The Brady Bunch." She left "Little House" in 1982 and appeared in a few television series, including "The Equalizer" and "Murder, She Wrote."
After a short romance with Lorenzo Lamas and Frank Sinatra, Jr., Anderson, now 47, married television writer and producer Michael Sloan. They have two children and live in Canada.
Anderson has continued to act occasionally, mostly in television movies. Her most recent role was playing the first lady in the 2006 NBC miniseries "10.5: Apocalypse."
quicklist: 4category: title: Katherine MacGregor/Mrs. Olesonurl: text:
Katherine MacGregor is still beloved for her comedic role as Mrs. Oleson on "Little House."
"That woman's a genius," Arngrim told ABCNews.com. "She's absolutely hilarious."
Now 85, she retired from acting after the series ended. Arngrim said she still takes in stray animals and people and "she's still bossing everyone around."