Randy Heiss, of Patagonia, told the Arizona Daily Star that he was walking his dog Dec. 16 when he spotted a red balloon.
Heiss thought it was trash but then saw a note in Spanish tied to it.
The letter to Santa was signed “Dayami.”
Heiss asked Nogales, Sonora radio station XENY AM for help.
The station posted about the balloon on Facebook and soon located 8-year-old Dayami Ianzo.
Heiss and his wife last week bought gifts for the girl and her sister and crossed the border to deliver them.
Heiss, whose son died in 2009 and has no grandchildren, says the experience was healing.