In a horrifying surprise dog attack, 12-year-old Niki Chrysanthopoulos sustained serious injuries to her face after the family’s pet dog mauled her as she leaned in to give him a kiss.

Niki was eating a snack on the couch before a karate lesson on Thursday afternoon when the family pet, an American Bull Terrier named Ollie, started growling at her, it was reported by NCA NewsWire.

She told the dog not to growl and went to kiss him on the head, but Ollie suddenly turned and bit her face, leaving a huge gash on her chin and pulling a chunk from the young girl’s lip.

Her mother, Tanya Chrysanthopoulos, who was on the phone at the time, was “frantic” upon witnessing the unexpected scene.

She immediately called out to her husband, who rushed to the scene. “I said I would ring an ambulance but he said, ‘there’s too much blood’,” Tanya recounted to 7 News.

With a towel under her lip and blood pouring from her face, Niki was urgently taken to the hospital by her father.

Ms Chrysanthopoulos shared that she received a call from her husband as they were en route to the hospital in Melbourne, informing her that the dog “had to be gone” by the time he returned home.

In response to the incident, the mother called Baw Baw Shire Council and reported the attack. A ranger promptly arrived at their home to take Ollie away and put him down.

Screenshot of Niki Chrysanthopoulos and her mother describing the horrifying event, as seen on 7News.

Ms Chrysanthopoulos said that Ollie, who was under three years old, had always been “overprotective” of the family. However, after the attack, she could no longer trust him and made the decision to surrender him.

“I really don’t care … it broke my heart saying that, but he’s eaten my daughter,” she said.

“How do I know if people come over that he won’t do it again? My poor baby is mauled, it’s horrific, I think I’m more traumatised than her,” Ms Chrysanthopoulos added.

Recalling the moment they parted ways with Ollie, she shared how the dog growled at her and attempted to bite her as she and her son lifted him onto the council ute.

This further reinforced her decision to let him go. “[My son] and I had to put Ollie in the back of the ute and say goodbye. So, I’m saying bye to my friend, my dog, but I couldn’t trust him,” she said.

As a result of the attack, young Niki has several loose teeth in her mouth and significant scarring to her face.

Ms Chrysanthopoulos divulged that surgeons had used 20 stitches on the outside of her daughter’s lip to pull the pieces back together, and even more on the inside of her mouth.

Niki remained hospitalised from Thursday to Sunday afternoon and may require further surgery as she recovers from the traumatic incident

The family has set up a GoFundme to assist with additional surgery costs: