Kim had taken to the social media site to tweet Katie, after seeing her and her ex-husband Peter Andre on the same flight.
She had tweeted: "Omg Katie Price aka Jordan and her husband Peter are on my flight home from NYC!"
The tweet was originally sent back in 2009 - when Katie and Peter were still married and trying to embark on a career in the US.
Sourcing out the tweet over the weekend, Katie finally decided to reply to The Keeping Up With The Kardashians star, tweeting on Saturday (16 January): "@KimKardashian awe that is so cute! Thankyou Kim #Flashback."
Katie's reply sparked some criticism from her followers on Twitter.
While some criticised Katie taking so long to reply back, others pointed out it was strange that Katie was replying to a tweet about herself and her ex-husband Pete, on the same day as her wedding anniversary with current husband Kieran Hayler.
One Twitter user commented: "@MissKatiePrice @KimKardashian 7 years later on anniversary to keiran tweets about you & pete!! Strange."
Katie and Kieran have been married for three years. The couple initially tied the knot on 16 January 2013 in the Bahamas, before renewing their wedding vows, following Katie's appearance on Celebrity Big Brother.
During their marriage, Katie found out Kieran had cheated on her with her best friend. While she vowed to divorce him at the time, Katie later chose to forgive Kieran and give their relationship another go.
The couple share two children together son Jett, two, and daughter Bunny, one. Katie is also mum to Harvey, Junior and Princess from previous relationships.
To mark her third wedding anniversary with Kieran, the mum-of-five shared a soppy video, a montage of their life together, which was accompanied by Katie singing the words to Vanessa William's 1994 hit 'Save The Best For Last'.
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