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Michelle Obama says she "can't make people not afraid of black people," but can "pick away at the scabs of discrimination" through her life's work.

"As people doubted us coming through - 'Are you Princeton material? Can you really make the grade?' Can you cut it?' - what do you do in those instances? All you can do is put your head down and do the work and let the work, your truth, speak for itself," the former first lady said Tuesday at the Obama Foundation Summit in Chicago.

"I can't make people not afraid of black people. I don't know what's going on. I can't explain what's happening in your head," Obama, 55, continued.

"But maybe if I show up every day as a human, a good human, doing wonderful things, loving my family, loving our kids, taking care of things that I care about - maybe, just maybe that work will pick away at the scabs of our discrimination. Maybe that will slowly unravel it.

"That's all we have," Obama said to applause. "Because we can't do it for them, because they're broken. Their brokenness in how they see us is a reflection of this brokenness. And you can't fix that. All you can do is the work."

The former first lady sat alongside her brother, Craig Robinson, for a wide-ranging discussion with author Isabel Wilkerson.

Her remarks on "doing the work" came after she praised the "freedom" that comes from winning a second presidential term. Securing another four years in office, Obama said, gives those in the White House the "luxury of just rolling up your sleeves, not worrying about what people are saying about your initiatives and your programs, and do what you think is right on a daily basis."

Earlier in the chat, Obama told Wilkerson, "Being the first black first family gave America and the world [the chance] to see the truth of who we are as black people, as others. That we are just as, and often times better than, many of the people who doubt us."

"But our stories don't get told," Obama added.

Some lighthearted, sibling rivalry-fueled moments also dotted the conversation in the Windy City. Obama ribbed her 57-year-old brother for seemingly having a difficult time using her formal title.

"I'm an adult, but I still can't believe that my sister is married to the guy who's going to be the next president of the United States," Robinson, a college basketball coach, recalled feeling.

"You still can't say the 'first lady,' can you?" Obama asked with a grin.

"It just doesn't roll off the tongue," Robinson replied to laughs.

"We'll work on that," Obama shot back.

"First lady of the United States ... FLOTUS," Robinson said with a smile. "She's Craig's sister."