A 9-year-old girl from Mexico drowned while trying to illegally cross into the United States, officials said this week. The girl, who wasn’t named, was on March 20 crossing the Rio Grande River with an adult woman from Guatemala and the woman’s child, a 3-year-old Mexican native. “Border Patrol Marine Unit agents responded to assist three individuals stranded on an island on the Mexican side of the Rio Grande River. Agents found the individuals and immediately began administering first aid while transporting the migrants to shore,” Customs and Border Protection said in a statement. Agents were able to revive the woman and her child but the 9-year-old remained unresponsive. Agents transferred her care to the Eagle Pass Fire Department’s Emergency Medical Services and she was eventually pronounced dead. A cause of death was not listed. Lt. Jason Mares of the Eagle Pass Fire Department in Texas told NBC that the incident …