Family historian Tracey Payne said the family came to Australia in 1920 and settled in Benalla and district.
“We have never got together as whole family before. In fact this will be the first time many in the family will meet,” Ms Payne said.
Tracey's mother, Mary Finch, had grown up believing her father was one of a couple of siblings.
However, when Tracey began a family research project they discovered he was one of 11.
“You didn’t ask about your family history back in those days,” Ms Payne said.
“Things were different back then and if a child was born to a unmarried couple it might be kept secret, for example.
“So you can imagine we found a lot of relatives we never knew existed.
“My maternal grandfather's family arrived on a boat in 1920, they actually came with eight of their 11 children.
“My grandfather was one of those eight.”
The family arrived in Melbourne originally and eventually settled in Benalla.
Ms Payne said the timing of the reunion was deliberate.
“So the significance of 2020 is that it is 100 years since the family arrived,” Ms Payne said.
“And the other big thing is that some of the cousins, the children of the 11 siblings, will be meeting for the first time.
“We have hired a hall and will have some food and drink, and a good opportunity to chat and meet people.
“We are also going to mark some unmarked graves in the Euroa cemetery.
“Two of the family are buried there, but as they were poor there were no markings; so we’ve organised to mark the graves and to put plaques on them.”
With only eight of the siblings coming to Australia in 1920, Ms Payne also tracked down a branch of the family in the United Kingdom, who are also attending.
“We have some coming over from the UK,” Ms Payne said.
“And some from Sydney, and the rest are a bit more local, coming from different parts of Victoria.”