Why is it that..

When my sister who is drunk as all heck wakes me up by ringing my phone twenty times last night  to go wake up dad to go pick her up from a pub at 3:30 AM it’s not considered rude but when I start singing the MacGruber theme song from SNL at 1:20 PM while she is sleeping off her hang over it’s very rude and inconsiderate? I mean it’s lunch time. I should be able to vocalize all I want. Harden the fuck up sister and deal with the consequences of drinking.

What is the difference between her waking me up last night and me having the potential to wake her up now?