A divorce, health concerns, a challenging child— personal problems— everyone has them.

Some people are better at setting them aside when they’re on the job than others. But personal problems that linger can hurt job performance, employee morale and your business’ health. Of course, the job could actually be a contributing source.

Here are some ways to spot employees who bring their personal problems to work.

Look for behavorial changes.

Every day, someone looks over the hogs to spot abnormalities in their behavior. But, does anyone watch employees as closely. Probably not.

Maybe a worker is hanging back or seems a little out of sorts. A change in behavior often indicates that something is wrong, says Don Tyler, a personnel-management consultant in Clarks Hill, Ind. “As with pigs, when something’s wrong, people usually show it.”

Behavioral changes are among the more obvious signs that a personal problem exists. Keep your eyes open for changes in these three key areas:

1) Interaction with co-workers.

If there’s a change in the way a person reacts toward co-workers a personal problem is likely plaguing him or her during work hours. In fact, personal problems often show up at work first, says Bob Milligan, a consultant with a business-management firm based in Madison, Wis.

One such example may be, if someone who’s normally easy-going snaps at co-workers over minor things. Everyone has the occasional bad day, but behavior like this can signal a nagging personal problem.

As another example, if an employee who is usually social with co-workers now distances himself from others or is abnormally quiet at more social-type gatherings.

2) Attitude.

A significant attitude change is another telltale sign. For example, if Joe is usually upbeat, enthusiastic and a motivator, but is now the one who needs encouragement, he’s likely struggling with a problem. Other similar signs might be if Joe’s usually chipper “good morning” isn’t as perky as usual. Perhaps he’s noticeably more pessimistic or makes remarks like “I don’t care anymore.”

3) Job performance.

“If a person feels differently, they behave differently. If they behave differently, they perform differently,” Milligan says.

More often than not, job performance turns sour when a personal problem surfaces at work. Everyone makes mistakes, but chronic slip-ups by an employee who’s typically careful about his work should send up a red flag. The same can be said for an employee who is normally punctual, but is now tardy on an ongoing basis.

Remember, “anything that’s out of the ordinary,” is a clue that something is wrong, says Tyler. However, be careful not to make assumptions too early. Look for patterns that develop over a period of time.

Personal problem or work problem?

Of course symptoms that might suggest a personal problem — bad attitude, poor job performance or a change in a co-worker’s interaction— can be difficult to distinguish from work-related problems.

For example, an employee that distances herself from a group could be a response to harassment on the job, or it could be a racial or cultural issue, says Tyler. Then again, a person’s withdrawal could be due to a personal problem that has led to depression.

Often, you won’t be able to tell the difference based on surface signs, getting to the root requires some careful inquiry. Milligan cautions, if there’s no job-performance concern, then someone else’s personal challenges are none of your business. While you may want to help an employee who is struggling with a personal problem, you need to tread carefully from a legal standpoint.

If an employee seeks you out for help, it frees you up to provide some advice and perspective. But the best option in that case is to offer to help find a professional, organization or service that has the resources to help with a specific challenge the employee is facing.