The study was conducted by researchers out of Columbia University in New York and Charles University in Prague, and their findings were published in the Journal of Psychiatric Research.

The study involved over 30,000 participants aged 50 and over, with 13,000 parents who had at least one son. The participants received regular testing of their mental skills, through tasks that challenged their word recall and mathematical abilities.

The researchers found one recurring theme throughout their data; parents of sons experience concentration issues and memory difficulties on a larger scale than those with daughters. For parents of multiple boys, it made matters even worse.

So, while they were able to determine that parents of sons experience cognitive decline at a faster rate compared to parents of daughters, they’re not exactly sure why.

The research team theorised that daughters are more likely to provide emotional, physical, and psychological support to their parents as they age.

Katrin Wolfova, the study’s lead author, explains this is because daughters often take on the role of informal caregivers while sons aren’t as well-equipped to offer the same level of emotional support.

The study does also reference other possible contributors to parents' cognitive decline, mentioning factors such as lifestyle, genetics and diet.