She was 16 years old and scared, but Maria Guadalupe Valdez made the two-day trek through the desert to come to the United States. Twelve years later, the 28-year-old illegal immigrant is caught up in the debate over illegal immigration, and that frightens her, too. She and her husband live in a tidy two-bedroom mobile home with their four U.S.-born children, ages 9, 7, 6 and 1, who motivate the couple to work long hours to build a better life for their family. But these American children also are a symbol of controversy. Opponents of illegal immigration call them "anchor babies" – a term considered by many to be derogatory, even racist, because it implies that Hispanics are having children as a way to stay in the United States. The thinking is that U.S.-born children of illegal immigrants help "anchor" the parents in the country and keep them from being deported.