"Sorry, you are not a child."
Translation:Scuze, tu nu ești un copil.
I think it's because of context. "Îmi" is about the speaker. I always equate "Îmi pare rău" to the English slang "My bad," because it's something the speaker is personally sorry or responsible for. Maybe I am wrong?
according to my Romanian friend(s) 'scuze' is less formal than 'îmi pare rău' and it would be weird to use it when it's not actually 'My Bad' however, if your dog died for example i would say 'îmi pare râu' as in 'I'm sorry' and 'condoleanțe' (if I'm spelling that right) is even more formal and specifically 'my condolences' 'mea culpa' is also used, apparently.