A restraining order had just been filed against the father accused of kidnapping his 18-month-old son from a Canton daycare Thursday, according to court documents. Just two days before Nathan Dorosario Sr. allegedly took his son, Nathan Dorosario Jr., from a daycare in the area of 1 Wellness Way in Canton, his son’s mother had taken out a restraining order against him, the documents said. The boy’s mother cited harassment and threatening words by Nathan Dorosario Sr., according to the documents. Dorosario Sr. allegedly suggested he would cause a scene at his son’s school if his son’s mother did not respond to his messages. Then, on Thursday, Dorosario Jr. was reported to be kidnapped at around 3 p.m. About 90 minutes after first reports, the boy and his father were found in a parking lot in Pawtucket, R.I., officials said. The younger Dorosario was taken from his father’s arms on Webster Street and placed into an ambulance for evaluation. Dorosario Sr. was arrested and is expected to be arraigned Monday as a fugitive from justice in Rhode Island. It is unclear when he will return to Massachusetts.