Madison, who appeared alongside Wilkinson on the TV series "The Girls Next Door," said while she has been fitted for the bridesmaid dress, she knows few details about the wedding attire, People.com reported Friday.
"I actually just got measured for my bridesmaid dress," Madison, 30, said Thursday. "(But) I haven't seen it."
"It's in the very preliminary stages. They didn't show me a sketch or anything. Next time I'll get a feel for the shape, I guess."
People.com said Wilkinson, 23, is to marry NFL star Hank Bassett in June at the Playboy Mansion in Los Angeles. The playmate previously indicated she would prefer a lavender-themed event.