Originally Posted by
canadiancow
I would agree with you if the security guard had been wrong and the GA right. But that was not the case.
I may be missing something, but wasn't the GA right? The AC website explicitly states that "Immediate family members (including spouse, common-law, same sex partner and dependent children) may board at the same time as Altitude Super Elite 100K, Elite 75K, 50K, 35K or Star Alliance member, even if not travelling on the same reservation." so wouldn't one's sister constitute as immediate family?