A Washington state couple became unwitting players in a kidnapping investigation this week after discovering that the 2-year-old child they were babysitting had been abducted and was the subject of an Amber Alert seeking his return.

John Tuong, of Renton, Wash. told KOMO that his sister had asked Tuong and his wife if they could watch her boyfriend's son Tuesday night. Tuong's sister said she and her boyfriend were planning an overnight date and she would return to collect the toddler Wednesday morning. 

What Tuong didn't immediately know was that the boy and his mother had been kidnapped from their home in nearby Des Moines. Authorities had issued an Amber Alert for their return, but Tuong didn't know about it until Wednesday morning. 

"I'm eating my breakfast, I'm checking my Facebook, all of a sudden I see this Amber Alert for this child," Tuong told the station. "And it looks like this child in my bed, and I'm like, 'Oh my God! What's going on?' "

Tuong called police, who arrived to find the child safe and sound. 

Tuong's sister, identified by police as Alyssa Chang, was later arrested in connection with the abduction. Police believe Chang and the boy's grandmother went to the boy's home Tuesday and shocked his mother with a Taser before driving to another house in Fife, where the mother was tied up in the garage. Police said the mother, who has not been identified, managed to free herself and went to another house to get help. 

Chang is currently being held in lieu of $250,000 bail for investigation of kidnapping, assault, and unlawful imprisonment. The boy's grandmother, who also has not been identified, later turned herself in to police. 

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