It happened Monday at a home on Sharptown Road in Laurel, Delaware around 3:00 p.m.
Police say the suspects, 30-year-old Daniella Blanchard and 23-year-old Ruth Blanchard went to the home of a 21-year-old woman over claims she was having a relationship with Daniella Blanchard's boyfriend.
The victim called 911, but before police arrived the Blanchards allegedly forced their way into the home and found the victim hiding in a bedroom holding the three-month-old, who is her nephew.
Police say the Blanchards began to assault the 21-year-old, who fell forward onto the baby.
Both the 21-year-old and the baby were taken to the hospital to be treated for minor injuries.
Another woman who went to the victim's aid was also hurt.
The Blanchards were sent to the Women's Correctional Institute each on $40,650 secured bond.