Video posted to Snapchat shows the accused girls putting the baby in the refrigerator, closing the door and laughing as the baby's screams are heard through the refrigerator door.
Then, the video showed a girl holding the infant as someone said: "See, she's OK!"
The girls were arraigned in Salem Juvenile Court on charges of child endangerment and assault and battery by means of a unsafe weapon, according to the Essex district attorney's office. The incident happened in Danvers, Massachusetts in the United States.
Their names are being withheld because of their age.
The pair had been babysitting the infant when they chose to put the baby, who was crying the entire time, into the fridge.
The child is said to be doing well and is at home with its family.
Bonnie, a mother of two, asked her niece and a friend to watch her 7-month-old daughter for a few minutes Monday evening, so she could take a shower.
"I'm traumatized from that", she said.
Brogna has told several news outlets she doesn't think her niece placed the baby in the refrigerator with the intent of harming her daughter.
The Department of Children and Families and local officials are now investigating the incident.
"You live, you learn and this is a lesson my niece will learn: to be careful who you leave your children with. You can't trust anyone, not even your own family", the baby's mother said.