Melissa Gilbert Engaged: She and Fiance Timothy Busfield "Looked Really in Love" on PDA Packed Date

USMagazine, Wednesday, January 30, 2013, 12:00pm (PST)

Half Pint is head over heels! As Us Weekly exclusively revealed, Melissa Gilbert is set to wed Timothy Busfield. (A rep for the Little House on the Prairie star, 48, first confirmed the news to Us on Tuesday,saying they "are both incredibly happy.") And although few were aware that Gilbert and the thirtysomething actor, 55, were even dating, it was extremely apparent to onlookers at Mr. Chow in Beverly Hills on Monday Jan. 29.

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"They were arm-in-arm the whole time," the witness says of the affectionate pair, who are both twice-divorced. After the romantic meal, the couple exited the eatery and "put their arms around each other waiting on the valet," the observer continues. "She was really sweet."

Hollywood friends for two decades, the pair quietly got engaged over the holidays, according to a source. Indeed, although they kept their romance under wraps, Gilbert and Busfield spent Christmas Eve 2012 together -- serving lunch to the homeless at the Los Angeles Mission Christmas Eve lunch and coyly posing for one of their first joint snapshots.

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Flash forward to Monday at Mr. Chow's, where the future spouses were more than happy to share their mutual affection in public. They looked really in love, really cute," the observer says. "Like teenagers or something!"

A mother of two, Gilbert's previous husbands are Bo Brinkman (they divorced in 1992) and Bruce Boxleitner (their split was finalized in 2011). West Wing actor Busfield, meanwhile, has three children, and has previously been been married to Radha Delmarter and Jenny Meriwin.

This article originally appeared on Usmagazine.com: Melissa Gilbert Engaged: She and Fiance Timothy Busfield "Looked Really in Love" on PDA Packed Date