Barack Obama's tears mid-tribute reveal a side of fatherhood rarely seen [Courtesy]

It was perhaps the greatest day for the 44th president of the United States, the opening of the Obama Presidential Center in Chicago.

Standing before thousands, Michelle Obama turned toward her husband and prepared to do something unusual.

She was not going to talk about politics; she was going to talk about the man she knew.

"Barack, you’ve got to look at me," she urged gently.