My Co-Worker Makes More Money Than Me But Started When I Did

Dear Experts, I just found out my co-worker makes more money than me, even though she was hired at the same time I was. We do the exact same job and have the same level of experience, but she is getting paid $5K more. We are both recent college grads. I know she got recommended for the job by her mom, who is friends with our boss. However, I don't see how she is doing any more work, or brings any more to the job than me. How do I approach my boss about this? I don't think I can continue working here knowing how much more she makes than me! Here is how our CAREEREALISM-Approved Experts answered this question on Twitter:Q#358 Her pay not your business; usually bosses HATE when you compare. Make case why your work worth more money. (@uliaerickson) Q#358 ... show plan 4 future improvements. Present proposal at next review while requesting raise. (@ValueIntoWords) [2/2] Q#358 Prove your value - write out how u helped boss/company save time/make $$, etc. then... (@ValueIntoWords) [1/2] Q#358Salary is confidential. Want more$? Approach boss abt. ur value & demonstrated results. Not abt. earnings of another. (@DebraWheatman) Q#358 Another person's pay isn't your business. However, if you feel you can justify a raise, speak with your boss. (@gradversity) Q#358 Document UR value to organization & present case 4 increased salary. Cannot approach from: "she gets more than me." (@DawnBugni) [2/2] Q#358 You're angry because she negotiated a better starting salary than you? Same job doesn't have to mean same pay. (@DawnBugni) [1/2] Q#358 I used to be the other person in your question. But I negotiated my salary. Make your case next review. (@beneubanks) Q#358 It is unwise 2 ask 4 a match; not worth ur rep./job. Confidential info 'found,' alerts mngmt of employee’s focus. (@resumeservice) Our Twitter Advice Project (T.A.P.) is no longer an active campaign. To find an answer to the above question, please use the "Search" box in the right-hand column of this website.