The Flintstones may not have been so far-fetched after all.
A team of archaeologists have discovered the remains of the earliest known nuclear family - a Stone Age mother, father and two sons who lived more than 4,600 years ago.
The find sheds tantalising new light on the life of our prehistoric ancestors living at the dawn of civilisation in Europe. It also suggests that modern family values have been thriving since before the time of Stonehenge.
The family - who appear to have been slaughtered in a raid by a rival tribe - were identified from fragments of DNA in their skeletons. The boys were aged eight and four.
They were buried near three other graves containing the skeletons of nine others.
Many of the bodies had injuries - suggesting that they were victims of a violent raid from a rival tribe or village. One women had a stone projectile point in her spine, and another had a fractured skull. Several bodies had injuries on their arms and hands.
Dr Alistair Pike, head of archaeology at the University of Bristol, who took part in the study, said: "This is a particularly significant find because it is the first time we can conclusively prove a family has been buried together.
"Graves which have been discovered pre-dating this find show mass collections of maybe hundreds of skeletons thrown together.
"This grave could be a watershed in the rise of the significance of the family, as previous evidence shows that around this time inheritable wealth became an important factor in family life.
"Whoever buried the family obviously knew they were family and deemed it important they were buried together facing one-another."
The burials took place in Germany around the same time that Stonehenge was being erected in England.
The family were buried near three other graves containing the skeletons of nine other people in a Stone Age cemetery at Eulau in Saxony-Anhalt.
They were discovered in 2005, but the DNA tests have only just been completed.
The mother was aged around 35 to 50 - old age for those days. She was carefully laid to rest on her left side with her head pointing towards the rising sun. The father - who was between 40 and 60 - was placed in a mirror position.
However, unusually for the period, the boys were positioned facing their parents, the scientists report in the journal Proceedings of the National Academy of Sciences.
Another 13 bodies were buried near by around the same time.
Other couples nearby were touchingly buried face-to-face with their arms and hands interlinked.
Each of the graves contained at least one child - ranging from newborn babies to children aged ten years old. There were no teenagers or young adults.
Dr Wolfgang Haak of the University of Adelaide, who led the study, said: "By establishing the genetic links between the two adults and two children buried together in one grave, we have established the presence of the classic nuclear family in a prehistoric context in Central Europe - to our knowledge the oldest authentic molecular genetic evidence so far.
'Their unity in death suggests a unity in life.'
As well as discovering the family ties between the bodies, the researchers also studied the chemical make up of their teeth to find out where they spent their childhood.
Growing teeth contain tell-tale traces of the minerals and metals in the food that a child eats.
They found that many of the women spent their childhoods in a different region from the men and children. That suggests that women were marrying out of their families and moving to the location of their new male partners.
Dr Alistair Pike said: 'Such traditions would have been important to avoid inbreeding and to forge kinship networks with other communities.'
The remains are now on permanent display in the Landesmuseum Sachsen-Anhalt in Germany.
The changes faced by our prehistoric ancestors
The third century BC was the end of an era for our prehistoric ancestors.
It was the dying days of the Stone Age, a time when the old bone and flint tools which had served mankind for millennia were being replaced with new-fangled metals like copper.
New farming techniques - and new livestock - were arriving from the warmer lands of the south and east.
And people were on the move - crossing the English Channel, exploring the islands off Europe's coast and trekking across the continent.
The Neolithic farmers of Germany lived in small villages in rectangular homes made of wooden posts and twigs, covered in a thick layer of clay and chalk.
The roofs were thatched allowing smoke from the central fire to escape. The huts were large enough for a big family to huddle around the central fireplace.
By 2600BC prehistoric families had been farming for thousands of years.
They were skilled at growing wheat and barley, and keeping pigs, cattle and sheep.
Dogs had been domesticated and would have been used as companions as well as protection.
They used the wheat to make bread and cakes, and possibly even beer.
They still gathered what food they could from the wild - apples, nuts, cherries, honey, peas and berries.
Although Neolithic means new stone age, it should really be called the copper age. Copper axes and knives were used by the wealthy - although stone tools and arrow heads were more common.
The clothes were simple. They wore leather coats and jackets, woollen leggings and maybe even simple shoes made from animal skins tied up with twine. They made pots and beakers, and decorated them with a distinctive cord design.
Almost nothing is known about their culture and beliefs. But the tender way they treated the dead, placing tools and jewellery around the carefully positioned body, suggests a belief in the afterlife.
In Britain at this time, society was organised enough to arrange the creation of the huge monuments of Stonehenge - using vast slabs dragged from Wales - and Silbury Hill, a vast mound of earth 130ft high.