According to the stereotype, they are usually overshadowed and overlooked.
But middle children are more likely to grow up to become successful and well-adjusted adults, a study has claimed.
Far from being apathetic or withdrawn, researchers found that a middle child's place in the family helps them develop negotiation and communication skills.
Psychologist Catherine Salmon claims that middle siblings are more likely to 'become agents of change in business, politics and science' – a conclusion that high-profile middle children such as Madonna and Bill Gates would probably support.
And they are also more likely to be faithful spouses, have the drive to succeed in the workplace and be motivated by fairness.
Professor Salmon, who reviewed dozens of studies into the effect of birth order for her book The Secret Power of Middle Children, said: 'As children, middles have to wait a lot. Modern middles wait while their younger sibling is loaded into the car seat'.
They wait while the firstborn performs in the recital. They wait to be served at the dinner table and complimented for their hard work in school. Middles are accustomed to not
getting what they want right away.
"They learn the art of delayed gratification, and this helps them later in life."
However, the picture isn't all rosy, as Professor Salmon also found that middle children report feeling more distant from their parents and are more likely to be easily influenced by
She added: 'Middles get less time, attention and resources from their parents, and they often suffer from this. But this suffering seems to be short-lived.'
'As is abundantly clear, this lack of attention can lead to the development of some extremely useful skills.'