Parents are often given all the credit - and the blame - for how their children turn out.
You get accepted into university, your parents are congratulated on producing such a smart child. You decide you'd rather be a Goth and do weird things with goat's blood, people say, 'I wonder where George and Martha went wrong?'.
As adults, plenty of us blame our parents for any (or all) of our shortcomings. But how much is their fault - and what can you do to change it?
According to a new study, our childhood affects our relationships for the whole of our lives - in quite a profound way.
Researchers at Harvard University analysed a group of men in 1938 and followed up with the same men over the years that followed until the men were into their 80s.
They found no matter what the socioeconomic background, the men with warmer, happier childhoods were better at relationships and had a more secure attachment to their partners.
Short-term studies on women by the same researchers predict the same might be true for women.
So if it feels like your family are still influencing your love life, years after you kissed goodbye to your pony posters or toy train set, you're probably right. Here's why...
What nature gave you: genes
The genes you inherit influence your personality and your relationships with other people.
One of the longest, most thorough studies of child development showed genes have a much greater effect on your personality than previously thought.
They're responsible for how well you do in school, how you get on with others, whether you choose a career as a corporate or a life of crime.
There's zilch you can do about genes, except be aware of what you've inherited and consciously fight against those that don't work for you.
What your parents gave you: environment
We don't just hatch out of an egg and raise ourselves.
We're dependent on people around us, and no matter how much our parents love us or how good their intentions, they're human and make mistakes.
After all, they have their own set of genes inherited from their parents, and how their parents brought them up influences the way they brought you up.
We're all products of the generation before.
Ideally, parents are loving, supportive and affectionate, while simultaneously encouraging their children to be independent and make their own decisions. That's the theory. Unfortunately, not too many of us grow up with perfect parents. Some parents are cold and distant, others cruel and abusive.
Most muddle their way through, alternating between Parents of the Year and 'Oh, for God's sake, what do you want now!' parents, depending on how far behind on the mortgage payments they are.
All parents have some flaws, and as a little child, you are like a sponge, soaking up whatever their attitudes are and reacting to the way they treat you.
Mum and Dad in the bedroom
Yes, that's not a sentence any child wants to read but one of the most important influences on the romantic relationships you have now is the relationship your parents had.
We learn how men treat women, how women treat men and how a relationship functions by the way our parents behaved toward each other. Scary thought, isn't it!
Now here's the really scary part: no matter what sort of relationship your parents had, you'll subconsciously search to find a replica of it, or (if you've consciously thought about it) the complete opposite.
Sometimes that's healthy. If you admired your parents' partnership, it's sensible to look for the same.
It's also sensible to want something completely different if you didn't.
The problem with all this is that we're naturally programmed to look for mum and dad clones.
Unless you're intensely aware of what your subconscious is up to, you aren't even aware of what's going on.
Fathers and daughters
The way women feel about their father affects the way they feel about all men.
He's the first man you meet, the first you get close to, so we tend to judge all men by him.
If your father was successful, you go out there thinking all grown-up men will be. If he was nice, all men will be nice to you.
If he wasn't so nice, you think quite the opposite. In fact, if you don't trust men, dad's usually got something to do with it.
The old theory that women who love their fathers marry a man just like him does have some truth to it.
If dad looked like Sean Connery on a good day, you probably are attracted to good-looking men.
If he looked like Mr Bean on a bad day, you'll probably be less impressed by looks and more attracted to personality.
But your partner doesn't have to look like dear old dad to be similar to him - they might be similar in personality, have the same gestures, expressions or even smell the same.
Often, it's the type of relationship you had with your father that you're trying to replicate.
If he was warm and wonderful and loved you no matter what, you'll probably try to find a guy who'll do just the same.
If dad was distant and didn't show any love or affection, unfortunately, the same thing can happen.
You may find yourself drawn to guys just like him - cold, uncaring men - because that's what you're used to.
That was your first male-female relationship, so it feels normal to you.
Mothers and sons
The same applies to mother and sons as it does to fathers and daughters.
If your mother was stunning, she could well be your blueprint for what you consider attractive in a partner - but it's still more likely you'll seek out the same type of relationship.
If you had a good relationship with your mum, it's likely you'll choose to settle down with someone who has the same personality type as her.
If she was a homebody and dad revelled in being looked after, you'll probably be attracted to a traditional girl who's happy to stay home, bring up the kids and warm your slippers by the fire.
If you thought mum sold herself short, you may consciously search for someone who's kicking ass in the boardroom.
The way your father treats your mother is your blueprint of how you'll treat women.
You learnt from dad when and how often to send flowers and Mum's response will dictate just how far you think wooing will get you.
The more carefully you look at the dynamics between your parents, the more you'll discover about your own relationship strengths and weaknesses.
Sisters and brothers
Parents aren't the only ones who have a huge impact on relationships - siblings do as well.
Women learn a lot from a close relationship with a good brother: it can set you up for a lifetime of easy, comfortable relationships with men.
Having a brother means you've got a walking, talking, live specimen of manhood to study during those angst-ridden, sexually formative years.
As an adult, you've got the male perspective covered by someone you know and trust.
Women with brothers tend to have a more realistic, rational view of men because they've spent time around males they're not sexually involved with.
There are lots of nice messages a (nice) brother can give you about how men treat women.
If you didn't have a brother, it's hardly your fault - but you're still better off than the girl who grew up with a not-so-nice male sibling.
Some brothers are outright cruel or unbalanced or cold and dismissive of sisters.
If your brother treated you as a second-class citizen, ridiculed you, criticised or ignored you, he sent a strong message about how other men will treat you.
A good brother-sister relationship celebrates the differences between men and women; a bad one reflects the age-old battle between the sexes.
Brothers and sisters
While your sister was surreptitiously studying you, you were doing the same with her.
Your sister-less friends were still trying to figure out how to get to first base, you were streets ahead in deciphering what makes girls tick.
You saw that women tend to be more emotional, noticed that she talked a lot, took a long time to get ready and that her girlfriends were important.
When you went out with a female, you understood her a little better.
Later in life, your sister's often the one you'll turn to for clues on why your girlfriend's upset when you wouldn't have the foggiest why.
As with women, if you didn't have any sisters, the opposite sex may seem a bit confusing.
If your mates were sister-less as well, you may have grown up to be one of those men who are fond of saying, 'I just can't work women out.'
If your sister was an out-and-out bitch, you grew up being highly suspicious of women.
The message you got from her: men are the enemy.
That doesn't seem true (you're nice, your friends are nice), so you reinterpret it to read: women are the enemy.
Happily, a few experiences with understanding, open girlfriends can break the mould.
Dating women like your sister at your own peril: it will reinforce your worst fears.