Brody, 34, is set to tie the knot with his longtime fiancée Kaitlynn Carter in Nihi, Sumba Island, any day now, but according to a source close to the family, Caitlyn, 68, “has work commitments that have been set up for months and couldn’t be changed in the end.”
Nevertheless, the source says “everything is good” between the two, adding that Caitlyn “will be throwing a big party for them when the newlyweds return to town.”
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Caitlyn, who shares Brody and his brother Brandon, 36, with ex-wife Linda Thompson, has been involved in the couple’s past wedding festivities, celebrating her future daughter-in-law in April when she attended her bridal shower at the Santa Anita Park racetrack in Los Angeles.
“Went to my first bridal shower,” Caitlyn captioned a photo of her and Carter, 29. “I had so much fun! PS so much better than Bachelor parties!”
“I’m so happy you were there!!!” Carter commented on the post. “It meant a lot to me!!”
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Other prominent family members that won’t be attending the nuptials? Brody’s half-sisters Kendall and Kylie Jenner, 22 and 20, respectively, whom he’s grown estranged from in recent years. (He recently admitted he was kept in the dark about Kylie’s pregnancy.)
“My two little sisters, we never even heard from them,” Brody recently told PEOPLE. “They never even RSVP’d, I don’t think.”
“We sent them an invite but we just never heard anything back,” he added. “Well, they’ll be missed. I would have loved to have had them there.”