First lady Michelle Obama and her mother, Marian Robinson, at a women’s college basketball game between the Princeton Tigers and the American University Eagles at Bender Arena Nov. 23, 2014, in Washington, D.C.
Mitchell Layton/Getty Images

First lady Michelle Obama’s mother, Marian Robinson, was initially “a little bit” leery about her daughter dating a biracial man, Robinson said in a 2004 Chicago TV interview that has resurfaced in light of a biography about Michelle Obama’s life that will be released next month.

During a sit-down interview with Chicago’s WTTW, which aired during Barack Obama’s 2004 U.S. Senate campaign, Robinson explained how her concerns had nothing to do her with being racist, but were more based on her own awareness of how difficult it can be for interracial couples and their biracial children.

“I guess that I worry about races mixing because of the difficulty—not for, so much, for prejudice or anything,” Robinson said. “It’s just very hard.”

Robinson also said that those issues would have come into play a lot more if President Obama were entirely white. “That didn’t concern me as much as had [Barack Obama] been completely white,” Robinson joked.

Michelle Obama’s biographer, Peter Slevin, said that his book Michelle Obama: A Life will be released April 7. According to the New York Daily News, the White House has not responded to inquiries about Robinson’s comments.

Read more at WTTV and the New York Daily News.