Image by Jason Reed / Reuters

First Lady Mrs. O returned to her pinstripe chalk stripe Alexander McQueen suit today as she began her campaign against childhood obesity. Mrs. O was joined by Surgeon General Regina Benjamin at a YMCA in Alexandria, Virginia, where they spoke on the issue.

This suit has certainly been a favorite of Mrs. O's in recent years. Mrs. O wore it several times on the campaign trail during 2007 and 2008, and for at least one public event last year. Click here to see our previous post the its history.

In the past paired with brooches, the first lady wore it with a high collar white shirt, red belt and coordinating lipstick for today's appearance.

Image by Mandel Ngan / Getty Images

Image by Mandel Ngan / Getty Images

First Lady Mrs. O is wearing a gorgeous wintery plum ensemble by Isaac Mizrahi for the president's State of the Union address this evening. What a fantastic moment for the great American designer, and the perfect style note for the State of the Union. In the course of his address, the president referenced two initiatives that Mrs. O will lead this year: the fight against childhood obesity and a new program to support military families (the latter co-led with Jill Biden). It's an inspiration to see such an example of style and substance in our first lady.

Purple was certainly the color of the evening, also reflected in Vice President Joe Biden's choice of tie and Congresswoman Nancy Pelosi's lavender suit. Several of you have observed that purple is the coming together of red and blue. One can't help but wonder if indeed the choice of purple was a deliberate effort to symbolize political unity and bipartisanship. Are we reading too far into the clothes? Or might this be another occasion that Mrs. O and company have used fashion to convey a powerful message?

Update: You must watch Isaac Mizrahi's video blog about his reaction to seeing the first lady in his design last evening. Love this!

Official White House Photo by Pete Souza

Thought a few of you might enjoy this! Peter Soronen is the design genius behind several of the first lady's most glamourous looks, including the purple chiffon gown Mrs. O recently wore for the Kennedy Center Honors. There are sure to be treasures found at this sample sale!

Images by Tim Sloan / Getty Images

The first lady gave a speech to the Joint Armed Forces Officers Wives Club at Bolling Air Force Base in Washington, DC today, where she announced the president's proposed funding for military family support programs -- a record $8.8 billion. For further reading, click here.

Mrs. O wore a teal green herringbone sheath dress, accessorized with a black flower brooch at the shoulder for the event. Designers TBD.

Image by Jim Young / Reuters

First Lady Mrs. O was greeted with a warm welcome as she arrived to speak to employees at the Department of Commerce in Washington, D.C. today. For the event, Mrs. O wore a gray sheath dress with three-quarter length sleeves, featuring a row of buttons that create a diagonal empire waist line. Quite inventive!

Update: Reader JW writes: "This is Alexander McQueen, Fall-Winter 2008-09. He did this dress in black as well as grey." I've confirmed that, indeed, this dress is Alexander McQueen from the "last season prefall collection."