A study published recently in the journal Proceedings of the National Academy of Sciences found evidence that some people whose parents divorced during their childhood may be at increased risk of health issues later. Not everyone whose parents divorced was affected, however. The increase risk was only observed in those whose parents hadn’t remained on speaking terms after the divorce.

Researchers at Carnegie Mellon University divided 201 healthy adults into three groups for the study. The first group was made up of people whose parents had remained together throughout their childhood. The second was composed of people whose parents had divorced during childhood but who had remained on speaking terms afterwards. The third group was made up of people whose parents had divorced and then broken off communication.

“We interpreted this to the extent that having parents who were divorced and not on speaking terms is probably an indicator of lots of acrimony in the family environment and sort of a lot of ongoing stress there,” one of the study’s co-authors told Newsweek, “that then translates downstream to having an impact on the immune system.”

To test that, the researchers exposed all of the participants to rhinovirus 39, a form of the common cold. They then monitored the participants to see how many of them developed the virus.

The results were pretty striking. The group whose parents’ divorces were followed by a breaking-off of contact were more than three times as likely to catch the cold. Presumably, that meant their immune systems didn’t respond as effectively when they were exposed to the virus.

Interestingly, the group whose parents had divorced but stayed in contact ended up catching the cold at the same rate as the group whose parents had not divorced during childhood. Assuming that continued contact between the parents represents a less stressful environment for the child, the findings appear to indicate that more positive co-parenting had a protective effect on the children’s long-term health.

There are many reasons why it’s important to work as positively as possible with your child or children’s other parent after a divorce. For one thing, Ohio law encourages shared parenting arrangements so that both parents may have frequent and continuing contact with the children, as long as such an arrangement is in the children’s best interest.

This observational study marks one more example of how positive time-sharing between parents appears to make a long-term difference in children’s lives.