How to handle co-workers having a higher salary

It's not the best situation. They don't say "Ignorance is bliss" for nothing.

If you don’t say anything to the person who can increase your compensation, you might start caring less about your work, which could be noticed. Worse, you might start having feelings of resentment towards the company, manager or even your colleagues, depending how much you like them.

If you ask for a raise without mentioning your colleagues, and don't get it, you won't be too happy knowing what you know. Or to be more specific, believing what you believe, that you deserve the same compensation as your co-workers.

If you ask for a raise, don’t get it and then bring up your co-workers, I assume this would prompt your manager to give you reasons why your situation is different. But it's possible you might think these reasons are BS.

These are, of course, hypothetical scenarios, but it's not bad to consider them.

Discuss with your manager and find out why. Ask them to be honest with you. Ask if it is something you can change. Maybe they just negotiated a better salary than you did. Maybe they have experience that you do not. If you do not agree, you could skip-level to their manager if your company supports that. Beyond that, if you are not satisfied with the answer, consider looking to other opportunities without hinting this to your current employer.

Try boosting your self-promotion, don't lose good morale and when you feel it's the right moment - talk with your manager about your expectations.

They may have more experience, handled larger incidents, went to a better school, had better job history.

There's nothing to handle, it happens.