Teenagers with more siblings have worse mental health, study suggests

Study of children in US and China found larger impact when brothers and sisters were closely spaced in age

From Cain and Abel and the Brothers Karamazov to Cinderella, the warmth and support provided by siblings has hardly been taken for granted.

Now, researchers have found that children who moan about their brothers and sisters may have good reason to complain: the more siblings teenagers have, the more it hits their happiness, they claim.