AP Photo/Eduardo Verdugo
First lady Michelle Obama walks down the presidential airplane upon her arrival in Mexico City on Tuesday, April 13, 2010. Michelle Obama is on a three-day visit to Mexico.
AP Photo/Dario Lopez-Mills
First Lady Michelle Obama, right, greets Counselor Maria Teresa Mercado, deputy director of the office of protocol of Mexico's Foreign Relations secretary upon her arrival to the US embassy in Mexico City, Tuesday, April 13, 2010. At center is U.S. Ambassador to Mexico Carlos Pascual.
AP Photo/Dario Lopez-Mills
First Lady Michelle Obama, left, stands with Mexico's first lady Margarita Zavala near an Aztec calendar in the National Anthropology Museum in Mexico City, Wednesday, April 14, 2010.
AP Photo/Eduardo Verdugo
First lady Michelle Obama, left, and Mexico's first lady Margarita Zavala visit to the National Museum of Anthropology in Mexico City, Wednesday, April 14, 2010.
AP Photo/Eduardo Verdugo
First lady Michelle Obama, right, and Mexico's first lady Margarita Zavala acknowledge members of a children's orchestra during a visit to the National Museum of Anthropology in Mexico City, Wednesday, April 14, 2010.
AP Photo/Dario Lopez-Mills
Students at the Siete de Enero primary school stand behind a banner welcoming first lady Michelle Obama to their school in a low income neighborhood of Mexico City, Wednesday, April 14, 2010.
AP Photo/Dario Lopez-Mills
First Lady Michelle Obama waves at cheering school children, not seen, at the Siete de Enero school located in a low income neighborhood in Mexico City, Wednesday, April 14, 2010.
AP Photo/Dario Lopez-Mills
First Lady Michelle Obama jumps as she dances with school children at the Siete de Enero school located in a low income neighborhood in Mexico City, Wednesday, April 14, 2010.
AP Photo/Dario Lopez-Mills
First Lady Michelle Obama greets school children at the Siete de Enero school located in a low income neighborhood in Mexico City, Wednesday, April 14, 2010.
AP Photo/Dario Lopez-Mills
First lady Michelle Obama, top center, listens to medical student Sofia Canales speak during a meeting with young leaders in Mexico City, Thursday, April 15, 2010.
AP Photo/Dario Lopez-Mills
First lady Michelle Obama embraces woman's rights activist Maricela Zurita from Oaxaca during a meeting with young leaders in Mexico City, Thursday, April 15, 2010.
AP Photo/Dario Lopez-Mills
First lady Michelle Obama, left, applauds a children's choir as she stands with Maria Teresa Mercado, deputy director of the office of protocol of Mexico's Foreign Relations Secretary, at Mexico City's airport, Thursday, April 15, 2010.
AP Photo/Dario Lopez-Mills
First lady Michelle Obama waves as she boards an Air Force plane upon departure from Mexico City's airport, Thursday, April 15, 2010.
