What You Bring to Work at 38 May Have Started at Nine

We tend to talk about adults as if certain qualities simply appeared one day. One person is optimistic. Another recovers from setbacks unusually fast. Someone gets handed a task they have never done before and thinks, “I’ll figure it out.” Someone else sees the same problem and is mentally already living on a goat farm in Portugal because apparently that felt easier than answering one difficult email.

We call it personality, mindset, confidence, resilience, attitude. But what if at least part of it started much earlier?

A 2026 study published in the Journal of Adult Development offers an interesting clue. The researchers used data from the Fullerton Longitudinal Study, which began all the way back in 1979 and followed the same people across decades. When the participants were between nine and seventeen years old, their family relationships were assessed every year. Importantly, this was not a group of adults in their late thirties trying to remember how supportive Mom seemed sometime around 1987. The relationships were actually rated at the time, both by the children and independently by their mothers.

Years later, the researchers returned to the same people at ages 29 and 38. This time, they were interested in something called Psychological Capital, often shortened to PsyCap. It consists of four…