Tenant requested ceiling repair

[Sean Maginess]

I just finished rehabbing a two bedroom apartment in Worcester, Mass. We put in a brand new kitchen with appliances, redid the bathroom, and replaced flooring throughout.  The unit has a popcorn ceiling.  At some point, there must have been a minor leak from the apartment above (that we don't own) because there is a small stain on the ceiling. It's totally dry with no signs of mold and when we were doing the other work we decided to let it be instead of having to redo the entire ceiling in the living room/ kitchen. Any repair just to the small, affected area would have been noticeable and worse than the small stain.  We rented the space for Feb 15 and the tenant is requesting that we cover up or fix the area because it is unsightly.  This is by no means a luxury apartment, but we used quality materials and products that would last.

What is the best way to tell the tenant that we aren't repairing it?