Conflict is a part of every relationship even working relationships.  The best way to address conflict is to push back on the employee to demonstrate self-leadership and attempt to resolve the conflict on their own.  

First, listen with empathy.  Depending on the number of your staff, it can be difficult to respond with empathy to frequent employee issues.  Keep in mind that often, all the employee is seeking is validation of their feelings. Demonstrate empathy by listening for a period of time that you are comfortable with.  When that boundary is extended, let the employee know that you value their employment and understand their feelings. Then redirect the employee by saying that you believe in them and their professional ability to handle a level of interpersonal conflict and suggest that if the problem persist, they take the first step in handling the issue professionally.  

Don’t get pulled into the drama.  Have the employees solve the problem without you.  

If the problem continues after this first step, then management may step in and take further steps.  Often, employee “complaints” are little more than an employee’s desire to vent to their manager. Unfortunately, when a manager engages in minor conflicts, it can add gasoline to a fire that might have flamed out on its own. By an employee addressing the issue head on, it frequently clears up any misunderstandings

Should the conflict escalate to a level where management intervention is necessary, sit both employees down together so that they must answer questions in front of each other, which encourages a more honest exchange with less exaggeration. If it gets heated, end the conversation and let the employee know you can discuss again when they can remain professional.  If there are still two different stories that cannot be reconciled, ask if there are any witnesses, emails, texts or other factual evidence that can help to determine a conclusion. If there is no other evidence, however, the manager may have to conclude that there is not enough information to determine a conclusion, and all employees must move forward professionally.