Police were told up to five men forced their way into the back door of a home on Raleighs Road, Melton, around 11.55pm last night.
A woman, a teenage boy and a child were home at the time.
According to police, the armed men assaulted the nine-year-old child. They then assaulted and demanded money from the 51-year-old woman.
The 16-year-old boy ran from the home to get help, while the men fled after stealing a gaming console and mobile phone.
The child was uninjured but the woman was taken to hospital, although her injuries were not life-threatening.
Sergeant Megan Stefanec described the group as being African in appearance and may be aged between 16 and 20 years old.