Perrin and Mat could have a discussion at Merillor. Mat leaves to join Tuon and enjoys his first taste of married life, rejoins Perrin later in the book after bringing the Seanchen into an alliance with Rand, and comments to Perrin on married life.

I could also see Egwene saying something to Perrin later in the books. They both married idiots so that might foster some discussion. Or maybe I am mixed up and Egwene hasn't married Gawyn.