The Jonas Brothers star, 26, briefly dated Miley between 2006-2007, and took to the social networking platform to comment on the series of throwback snaps posted by the "Nothing Breaks Like A Heart" hitmaker.
The "Malibu" songstress has been posting a number of vintage pictures on her social media accounts since International Women's Day on Friday, March 8, sharing tributes to stars including Taylor Swift, Demi Lovato and Selena Gomez.
After the 26-year-old shared an old photo of herself wearing an old school Jonas Brothers T-shirt, she shared the post privatelly with the "Sucker" singer along with a message that read "lols".
The "Wrecking Ball" star went on to capture his response, reading, "Amazing. These throwback shots have been (fire)."
Joking about his positive response to the message, Miley shared a screenshot of the reply, writing, "That moment when even your ex knows your socials have been (fire)."
After the exchange was made public, Nick's wife Priyanka Chopra commented on Miley's post, subtly reminding fans that she is married to the "Jealous" star.
"Lol. Hahaha.. Hubby is right. These posts r (fire)," she wrote.
Nick recently praised the "Younger Now" singer during an appearance on Apple Music's Beats 1 radio show on Monday, insisting he's thrilled for her success.
"She's a real singer, but we knew that because we grew up with her," he said. "It's no surprise now that people are coming around to her (talent)."