Children with two or more siblings do worse in the classroom, according to a new study.
Academics at the University of Melbourne in Australia examined the results of more than 1,800 children aged eight to 11 and found that results in reading and numeracy were up to five per cent worse for children with two or more siblings than for those with one or none.
Boys from larger families were found to be affected more than girls.
Having more siblings also raised the risk of falling into the bottom two-fifths of the class and reduced the chance of featuring in the top two-fifths.
The study's co-author Julie Moschion, said: "Educational penalties for children from larger families occur – and the effect is greater for boys than girls. The size of a family is an often neglected issue in the discussion of educational outcomes."
Unhelpfully, the study doesn't suggest any solutions for those of us with three or more kids, but it did suggest that this under-performance could be caused by teachers' perceptions of children from bigger families.
It examined teachers' attitudes and found a 'negative bias' against children growing up in larger family units.
They were more likely to give lower assessments of the performance of children with two or more siblings.
In particular, teachers tended to believe that boys from larger families were doing worse in class than other children.
The researchers said the findings amounted to 'strong evidence for the existence of a quantity-quality trade-off'.
They said that 'increasing family size from two to more than two children results in an objective disadvantage in children's achievement through test scores'.
There was also a 'subjective disadvantage expressed by teachers' possibly because of 'stereotypes' they held about larger families.
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What do you make of these findings?