Eldest sibling's ego

I have a kid sister and a kid brother. We get along and I love them most of the time. Most. I can tolerate most things but not when they raise their voice at me! That's my trigger point. I snap when they do that. 

Today is one of such day. My sis have to scream at me cos I wore her shirt?! Damn selfish and damn rude. So calculative then I should start labelling everything that I bought for the house? Wtf. Super pissed just now. 

Call me old fashioned. But I really feel that they should respect me as an elder sibling. In the midst of our exchange of screams, the sister told me so what if you are older? Don't make you anymore senior. Seriously I have 3 more years of rice in my tummy than you bitch. And I could have stomp you out of my sight when you were a baby! Show me some respect. 

Is it just me? Or do all the eldest sibling feel the same way? The eldest sibling ego.