NEWS FLASH! I now know what caused the coolness between my aunt Angela and her stepdaughter, my cousin June.
My cousin Rob, who was part of the wedding party along with his longtime GF, said that June was jealous of Melinda (even though, as I noted previously, June's already married), in large part because June wanted to be MOH, the honor which she did not bestow upon her sister at her own wedding. Melinda was upset, but that did not stop her from doing her BM duties like showing up to dress fittings, or taking part in the festivities leading up to the wedding - bridal shower, bachelorette party, rehearsals, etc.
June did not show up to even one of these events - up to and including the rehearsal. Melinda was extremely upset at the rehearsal and rehearsal dinner; she was crying on her wedding day, but my cousin Rob calmed her down and consoled her (since it's bad luck for the groom to see the bride before the wedding) so that she was happy again in time for her groom to see her.
These are the kinds of things that are indicative of my cousin June's passive-aggressive and mean-spirited nature. She said that since she wasn't the MOH, it wasn't important for her to be there for her sister, forgetting that she herself had not made Melinda her MOH. My aunt (both girls' stepmom) says that June acts like the world "owes" her something, and she's just tired of it.
She tried to make good by helping out at the wedding, helping to serve dinner and etc; but that was too late for my aunt, who saw how she had treated her sister throughout the whole process of preparation for the wedding.
I hardly blame my aunt. My cousin June has gotten through life Mean Girl-ing and abusing and being cruel to everyone around her, me included. Quite a few of us are fed up with her.