-LRB- CNN -RRB- -- The toddler whose body washed ashore in Texas last month has been tentatively identified as a 2-year-old girl , and her mother and a man identified as her boyfriend were arrested Saturday , the Galveston County Sheriff 's office said Sunday . Police believe two-year-old Riley Ann Sawyers may be `` Baby Grace . '' Investigators believe the child they dubbed `` Baby Grace '' is actually 2-year-old Riley Ann Sawyers , the Galveston County Sheriff 's office said Sunday . DNA analysis is still in progress to confirm that identification . The child 's mother , Kimberly Dawn Trenor , 19 , and a man identified as Royce Clyde Zeigler II , 24 , were arrested Saturday on charges of injuring a child and tampering with physical evidence , the sheriff 's department said . The couple lives in Spring , Texas , a Houston suburb about 75 miles north of Galveston . Their bonds were set at $ 350,000 each . The arrests followed searches conducted Saturday after a November 7 tip , the sheriff 's department said . Deputies and FBI agents plan to release more information at a news conference Monday , Galveston County Sheriff 's Maj. Ray Tuttoilmondo said . The girl 's grandmother , Sheryl Sawyers , of Cleveland , Ohio , told CNN affiliate WKYC that Riley Ann has been missing since June . Watch Sawyers family describe their fears before child was identified '' On October 29 , a fisherman discovered the body in a blue Sterilite plastic container on an uninhabited island in Galveston 's West Bay . Police dubbed the dead girl `` Baby Grace , '' and asked the public for help in identifying her . A medical examiner said the child 's skull was fractured , and a forensic dentist estimated her age at 2 to 3 years . In composite sketches , the girl is wearing a pink skirt and matching top -- clothing authorities said she was wearing when she was found . The other sketch , a close-up rendering of the child 's face , shows a fair-skinned toddler with long blond hair . `` She is more to us than just a case number , more to us than just an unidentified body . She is very much a human being , '' Tutoilmondo said last month . `` She is someone 's child , someone 's grandchild , someone 's cousin , someone 's best friend , and to us , that is the most important part about this case . '' `` We have adopted the name of Baby Grace because , there again , that is part of the emotional part of this case for us , '' he said , holding a tiny sneaker identical to one of those the child was wearing when she was found . E-mail to a friend CNN 's Hank Bishop contributed to this story .