LOS ANGELES, CA (Catholic Online) - While the 14th Amendment to the Constitution stipulates that those children automatically become U.S. citizens, some members of Congress wish to change that provision.

The effort, part of the ongoing debate over illegal immigration, in particular people from Mexico -- has created some controversy.

"This has got a lot of attention in the past weeks," Jeffrey S. Passel, the study's author says. "The idea was just to put a number on it."

The study found that 79 percent of the 5.1 million children of unauthorized immigrants in the United States were born in this country, making them U.S. citizens.

In addition, nearly one of four children born in the United States in 2008 had parents who were immigrants, the Pew study found. Of those, 16 percent of the parents were legal immigrants and 8 percent were in the United States without proper documentation. Passel says that many of those children are Latino.

More than three-fourths of all unauthorized immigrants in the United States in March 2009 were Latinos, the researcher said. And nearly one of every four children under age 18 in the nation was a Hispanic.

"Overall, Hispanics who live in the U.S. have higher rates of fertility than do whites, blacks or Asians," the report states. "And among Hispanics, the foreign born have higher rates of fertility than the native born."

IN spite of this, a majority of Americans seem to oppose changing the 14th Amendment. A nationwide poll conducted in June by the Pew Research Center for the People & the Press found that 56 percent of Americans are against changing the citizenship provision while 41 percent favor amending it.