They made their red carpet debut together just this week at the NBC upfronts.
Lindsey - nee Kildow - was married to fellow Olympic skiier Thomas Vonn from 2007 to 2013.
She also dated Tiger Woods from March 2013 to May 2015.
Smith's cousin told Radar Online that the relationship is 'awesome' so far, but she is not 'allowed to talk about it'.
Last month she said the 'break-up was hard' and that the experience has mad her stronger The 14-time major champion aborted his previous planned return after over a year out of action following his latest surgery on a serious back injury.