Natisha Hillard, 27, sold her baby girl to Christopher Bour, 41, who molested the infant and used her to make child pornography.
Bour, who paid Hillard $500, was jailed for life, plus 55 years in 2014 after admitting to the horrific abuse.
Hillard, from Gary, Indiana, admitted selling her infant daughter to be used in child porn and was in the room during one of the grim encounters.
Photographs and videos seized by the FBI showed Hillard with her daughter, as well as images of Hillard's other daughter, who was three years old at the time of the abuse.
Police began investigating Bour after being alerted by an unnamed masseuse who said Bour had texted her about his intentions to sexually abuse the four-month-old child.
One of Bour's messages read: 'U wanna watch me play with a baby tomorrow a real one.'
Another said: 'I get a chance once in a while I was just seeing if you would hold the camera.'
The woman told FBI agents she had seen child porn movies on Bour's laptop during previous visits to houses he lived in while renovating them. She also said he had expressed interest in 'animal love'.
An FBI agent assumed the identity of the masseuse and texted Bour about what he planned to do with the infant.
Bour responded with graphic descriptions, said he had done it before and that the mother approved.
FBI agents raided Bour's home in Hammond, Indiana, and seized his computer.
They found videos and photographs of people engaging in sex acts with pre-pubescent children, including images of Bour and young children. Hillard could also be seen in some of the photographs.
Court records showed the mother met Bour through an internet dating service.
Bour admitted buying a child for sex, possessing child pornography three counts of producing child pornography, CBS Chicago reported in 2014.
His defense team asked for him to be given the minimum sentence - 30 years - but he was jailed for life plus another 55 years, to run consecutively.
District court Judge Rudy Lozano said Bour's crimes were 'horrific' and the evidence was 'disgusting'.
During his sentencing, attorney Jill Koster said: 'There are some crimes so horrible that the defendant doesn’t deserve a second chance.'
Hillard was sentenced to 24 years for child pornography and endangerment.