A 13-year-old girl suffered a collapsed lung after she tried to protect her 11-month-old nephew from a gang of men armed with machetes, her family has said.
Relatives said the teenager needed 300 stitches after the men forced their way into a house on Trasna Way in Lisnaskea, County Fermanagh, at about 21:15 GMT on Saturday.
The baby was unharmed.
The 13-year-old is ill and in a stable condition.
Fr Jimmy Mc Phillips, a local priest, said the attack was "horrific".
"It has horrified the community and greatly disturbed this town, a community that by and large lives very peacefully together," he said.
"All nationalities and cultures are represented within this community and comfortably live together.
"We are praying that this indiscriminate attack is a one off."
The police have begun an attempted murder inquiry.