The incident occurred as the two were seated next to a 60-year-old man on an Atlanta-bound flight on Feb. 8.
The 2-year-old boy reportedly started to cry as the plane got ready to land. Jessica Bennett said that's when Joe Hundley called the boy a racial slur and told her to "shut the baby up."
She said Hundley then took it a step further and slapped her son Jonah.
"I could not believe he would say something like that to a baby or about a baby and then to hit him," Bennett said. "I felt like I was in another world. I was shaking."
Other passengers then came to her aid and the two were given a new seat.
Since the incident, Bennett said the toddler has become apprehensive of strangers.
Hundley faces a federal assault charge. His attorney said he will plead not guilty.
