I have a very good friend who has regular parties/ gatherings etc. Rarely does he invite me. I always go. And it usually happens the way you described your situation. Some one else calls me and asks if I am going, do we want to ride together etc. It is very possible your sister found out that others had spoken to you and so she didn't call you herself, b/c she figured you knew. Also, if you know A LOT of people-like poeple in GLO's do, it is hard to actually call and invite everyone. Word of mouth is the way the word gets out. I am sure your sister wanted you there and your presence was obviously missed. It is also a little bit possible she is wondering why you didn't come to her party and her feelings are little hurt too.
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