The photo dates back to six and a half years ago when the childhood sweethearts were on holiday.
Captioning the photo shared via Instagram, Arg said: "Here's a #ThrowbackThursday for you... @lydiabright and I 6 1/2 years ago on Hol! #TrueLove #SoulMates #BestFriends x."
Aww, how sweet!
Arg and Lydia's romance has been well-documented on the reality show, with the pair having their ups and downs and going through break ups and arguments.
But, they made a final promise to be together forever during the 14th series finale in April, and since, they've gone from strength to strength.
Last month, the lovebirds celebrated their seven-year anniversary.
Lydia said at the time: "Seven years ago today, I met this one at the Duke of Essex Polo. Never did I ever think that we would be where we are today. We battled some storms and jumped many hurdles. But despite everything we made it this far. You love me unconditionally, charm everyone with your infectious personality and make me the person I am today. Love you always and forever. Happy anniversary x."
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