Start by discussing the issue with the employee privately. If this behavior has been going on for a while, then there might be something in your employee’s personal life that you aren’t aware of. Even if it turns out the employee just struggles with waking up early, at least you’ll have a better understanding and didn’t publicly shame them in front of their colleagues for their lack of punctuality.
Work with the employee to develop an equitable solution — such as staying later in the day at the office to compensate for arriving later. Ultimately, you may have to be firm with meetings and company events and require the employee to show up on time just like everyone else. Leadership is a lot about being equitable. Employees want to feel as it you are treating them equitably and fairly and not letting one or two employees have special treatment.