Science claims to confirm that eldest children are in fact, the best.

New research in the Huffington Post has found that older siblings are smarter, with higher IQ than others.

Researchers believe that's down to environment, as older brothers and sisters often teach the younger ones, and parents have less time for each as the family grows.

They're also allegedly more responsible, and more successful - possibly because they're eager to please their parents.

And, it's claimed that the eldest children follow the rules and are more agreeable than younger siblings.