Caption: FILE - In this June 9, 2009 file photo, actress MelissaGilbert appears at Borders Books to promote her autobiography "Prairie Tail" in New York. Gilbert will be among the 12 celebrity contestants on the next season of the ABC dancing competition, premiering March 19. (AP Photo/Charles Sykes, file) Actress Melissa Gilbert in 2009. (Charles Sykes/AP)

It’s been 32 years since the final episode of the pioneer drama “Little House on the Prairie,” but that doesn’t stop folks who wished they grew up in Walnut Grove (come on, admit it) from peppering actress Melissa Gilbert with questions about what life was like on a 19th century farm.

Yeah, here’s the thing: She has no idea.

“Actually that would make me a couple hundred years old. I know I look it sometimes,” joked Gilbert, repeating a line she’s delivered nearly as many times when fans (especially the young ones but not always) confuse her with Laura Ingalls, the precocious character she played from age 9 until 19.

For about an hour on Saturday, Gilbert entertained more than 100 “Little House” heads with one-liners that belied the family-friendly wholesomeness of the show with which she is inextricably linked. The crowd arrived at the National Archives with umbrellas and the actress’s new book, “My Prairie Cookbook,” in hand and got a lot more than the standard author-answers questions program.

Gilbert’s first target? Herself.

She said of her recent move from Los Angeles to small town Michigan, “I’m tired, at 50, of trying to be a size 2. And now my forehead can move!”

Gilbert even shared a tale most actresses of a certain age would take to their graves: A stranger once said to her, “You know you look just like Melissa Gilbert, before she had all that work done on her face.” Ouch. And also, hilarious.

Next up on the chopping block was actor Sean Penn, whose father Leo directed three episodes of “Little House” in the mid 1970s.

“Sean Penn was one of the first people to pass out on set because of the heat,” said Gilbert. “I could take him on in a sauna. Man that came out wrong.”

Who knew “half pint” had so many punch lines?

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