Scheana Marie Shay and Katie Maloney remain as close as ever as they begin production on Vanderpump Rules season four.

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Although the two women butted heads for the first three seasons of the Bravo reality show, and had an on-and-off friendship, Shay and Maloney made amends last year, and months later, are still the best of friends.

"In honor of #NationalBestFriendsDay I want to say to these ladies how much I love you!!!" Shay wrote to Maloney, as well as Ariana Madix, on Instagram on Monday. "Thank you for always being here for me no matter what! #PumpRules."

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A photo posted by Scheana Shay (@scheanamarie) on Jun 8, 2015 at 2:31pm PDT

After rekindling her friendship with Shay during Vanderpump Rules season three, Maloney took to her blog, where she expressed her surprise in her newly solid friendship with her fellow reality star.

"When we both decided to bury the hatchet and get along ahead of Miami, I didn't know if it would be the same as it was with us," Maloney wrote. "What happened was not only did we re-kindle our friendship, but Scheana has become of my closest friends. Scheana has a huge heart and became a massive supporter of me and what happened with Tom and I this summer. Since then our friendship has grown, and I'm so thankful for her.

Vanderpump Rules season four is expected to return to Bravo later this year.