Mai Hyunh is a fictional character in the Hey Arnold! TV Series. Mai is Mr. Hyunh's long lost daughter, who was found by Helga and Mr. Bailey in the episode "Arnold's Christmas". Mai was given to American soldiers by her father, Mr Hyunh, at around 2-4 years old during the Fall of Saigon in 1975. She is referenced once in the episodes "Family Man" and "Chocolate Boy". It is possible that Mr. Hyunh was talking to her on the phone in the episode "Rhonda Goes Broke". She is also fluent in Vietnamese.