'Eldest daughter syndrome’ has long been an online phenomenon, with millennials talking about the added responsibility they felt growing up as the oldest siblings, but new research has backed up their claims and now science is on their side.
Being a sibling in a family of any size comes with unique challenges. For one, there's the ubiquitous challenge of sibling rivalry, though science has shown that kids who fight with their siblings will fare better in life, and surprising research has also shown that teenagers struggle more with their mental health when they have siblings.
