Emily disappeared from Springfield, Missouri on February 2, 2009. She was abducted by her non-custodial mother, Trina Sue Anne Atwell-Chavarria. A photograph and vital statistics for Atwell-Chavarria are posted below this case summary. A felony warrant for kidnapping was issued for her on February 13, 2009.

Emily's father, Roy Koyama, was engaged to be married to Atwell-Chavarria. The wedding was set for August. The couple planned to move into a new home on February 7. Roy has two other children from a previous marriage in addition to Emily, and Atwell-Chavarria has another daughter. Roy stated he met Atwell-Chavarria in 2007 and she moved into his apartment, but they decided to break up after she'd been living with him only a few weeks. Roy said Atwell-Chavarria then announced her pregnancy, and he decided to marry her to provide a stable home enviroment for the children. He stated in October 2008, Atwell-Chavarria had him sign a consent form so Emily could get a passport for an upcoming family reunion in Costa Rica, where Atwell-Chavarria is from. The family reunion never happened. Roy came home from work on February 2 and found his fiancee and baby gone with most of their belongings. Atwell-Chavarria left behind a note accusing Roy of abusing her, an allegation he denies.

Atwell-Chavarria claims she took Emily because she was concerned for the baby's safety. She stated Roy was a physically and emotionally abusive partner as well as a drug addict. She claims she got two orders of protection against him, but he violated the orders and remained in contact with her.

Authorities have determined that Emily is in Costa Rica with her mother. At the time of the abduction, Atwell-Chavarria was still legally married to another man who resides in that country. Roy worked through legal channels trying to force Emily's return to the United States. A Costa Rican court was supposed to settle the matter in January 2010 and Roy traveled there to attend it, but the hearing was postponed to February. Roy was able to see his daughter once in January before he returned to the United States.