According to The Daily Telegraph, Hackett and his girlfriend met through their mutual friend and fellow swimming legend Michael Phelps.
Back in May, Hackett, 37, shared a snap of himself alongside Schmitt (left) and her sister, Kristen (right).
"Great to see @arschmittyrecognised and rewarded for all her amazing work on mental health," he proudly wrote.
"Her sister @kirstengator got to present her with the award last night in NYC. An incredibly great person with a big heart - well deserved. Not to mention a 4 time Olympic Gold Medallist!!!! Huge achievements both in and out of the water," he continued.
The newspaper also reports that the two have been spending some time together at the gym and also enjoying a date in a helicopter while the 27-year-old visits her new Australian beau Down Under.
This article originally appeared on WHO.