A new study from U.K. researchers suggests that first born children are more likely to be nearsighted due to the added pressure from their parents to do well in school, according to the Daily Mail.
Researchers at Cardiff University studied more than 80,000 people from the ages of 40 to 69 and found that those who were first born in their family were 10 percent more likely to be nearsighted and up to 20 percent more likely to be severely shortsighted, according to the Telegraph.
Parents tend to be more cautious with their first born children and raise them at stricter standards in the early parts of their life, while they raise their younger children more lax.
"Greater educational exposure in earlier-born children may expose them to a more myopiagenic environment, for example, more time doing near work and less time spent outdoors," said Jeremy Guggenheim, lead scientist for the study. "Reduced parental investment in children's education for offspring of later birth order contributed to the observed birth order vs myopia association."
The risk factors were generated after the scientists ruled out other factors like "educational exposure" and an actual history of "eye disorders," according to the Guardian.
The numbers for children with short shortsightedness have gone up to 23 percent in recent years, more than doubling numbers found in the '60s.