BATON ROUGE - A father-son duo was sentenced to federal prison after sending each other child porn; the son did so while in jail for a prior offense. 

Bobby Wall Jr., 46, of Parchman, Mississippi, admitted during the trial that he used Facebook Messenger to send his father, Bobby Wall, 68, multiple images containing child porn. When he sent the images, Wall Jr. was in the Wilkinson County Jail. 

Wall told his son to "keep [the images] coming" and received 15 more from him. 

Investigators said, at a minimum, Wall Jr. had access to 100 images of child porn that he sent to himself through Facebook Messenger and then to his father. 

Wall Jr. was sentenced to 16 years in prison followed by 15 years of supervised release, and Wall was sentenced to just over 13 years in prison followed by five years of supervised release. Both will be required to register as sex offenders.