An experienced dog trainer believes there needs to be more education around socialising canines at an early stage.

It comes after an elderly woman in Northland was killed by a dog in the backyard of her Moerewa home on Thursday afternoon.

Two daughters of the woman in her 70s were also left injured by the encounter.

Family spokesperson Joey Rapana said they were devastated at the tragic loss of a dearly loved mother, nanny and aunty.

"No one would have expected such a tragedy in our community."

Rapana said his aunty's two daughters were still healing from their injuries.

"This is not the time to lay blame anywhere but a time to call for action to keep all our communities safe," he said.

"We are all here as a community to support our uncle and his whānau at this time."

Police confirmed that the dog was a household pet and were still investigating what happened.

Animal behaviourist Mark Vette said the socialisation of puppies during their first four months was critical.

"The formative periods [are] two to four months.

"That's the period when you learn to become social, you learn who your extended family is and after four months it normally starts closing down so if they don't get anything in that first four months it's a real problem."

Vette said the less socialisation a dog experiences the more territorial they become and getting dogs fully vaccinated promptly means they can be socialised sooner.

"Vaccinations can take between 10 and 14 weeks, depending on the vaccination you use... but you want [them] as early as possible, you want to be in that formative period."