were initially charged with injury to a child and tampering with evidence . But since the initial charges were filed last month the investigation has continued and police have gathered additional evidence , in addition to confirming Riley 's identity , said a statement released Wednesday by Galveston County Criminal District Attorney Kurt Sistrunk . Based on that , the grand jury was asked to upgrade the charges , he said . A three-hour hearing was held Wednesday in which grand jurors heard testimony from five witnesses , including police and FBI investigators and the medical examiner . The grand jury deliberated for only three minutes Wednesday before upgrading the charges , Sistrunk said . Trenor told police Riley had been beaten and thrown across a room and that her head was held under water before she died July 24 . She said the couple hid the girl 's body in a storage shed for one to two months before putting it in the plastic container and dumping it into the bay . A medical examiner said Riley 's skull was fractured in three places that would have been fatal injuries . Trenor and the girl moved to Texas from
-LRB- CNN -RRB- -- A Texas couple charged with killing the little girl known as `` Baby Grace '' now face capital murder charges , after a Texas grand jury upgraded the charges on Wednesday . Riley Ann Sawyers was moved from Ohio to Texas by her mother . Prosecutors said they have not decided whether to seek the death penalty against the girl 's mother , Kimberly Dawn Trenor , and Trenor 's husband , Royce Clyde Zeigler II . Two-year-old Riley Ann Sawyers was beaten to death and her body was disposed of in Galveston Bay . Riley 's body was found October 29 by a fisherman on an uninhabited island in the bay . It was wrapped in black plastic bags and stuffed in a blue , plastic bin . Her identity was not known at first , and police dubbed her `` Baby Grace . '' Police sketches of the child were widely distributed , and Sheryl Sawyers , the girl 's paternal grandmother , contacted police from her Ohio home to say the drawing resembled her granddaughter . DNA testing confirmed the child 's identity . Trenor , 19 , and Zeigler , 24 ,