First Lady Michelle Obama paid tribute to her mother Marian Robinson at a Mother's Day tea held at the White House. "There's no way that I could ever fully measure all that my own mommy has done for me," said the first lady, her voice breaking. "This woman who tries to take absolutely no credit for who I am, for some reason. She is my rock." She also praised her mother for always pushing her to be the best woman she could be, as a mother and as a professional. "As our family has grown, she's managed to expand her love for all of us. And raising our girls in the White House with my mom ... is a beautiful experience."