The popular beauty and lifestyle star took to her Instagram to announce the happy news to her 139K followers, who overwhelmed the bride-to-be with messages of congratulations.
Grace revealed that thoughtful Chris had chosen her father's favourite spot to get down on one knee, after she had left a red rose at her dad's grave to mark Father's Day.
"Actually can't believe it," Grace captioned a photo of the moment Chris asked her to be his wife, "still shaking! I'm the happiest girl right now and I love you so so much Chris, thanks for making my dreams come true and for being so thoughtful."
The couple's daughter Sienna was also involved in the special moment, sitting along the wall beside her mother, however Grace later said she 'hadn't a clue what was going on'.
In her Instagram stories, the bride-to-be gave her fans a sneak peek at her gorgeous ring when she posted a Boomerang of her and her new fiancé enjoying a glass of bubbles.
This morning Grace said that she was 'blown away' by the comments she and Chris had received congratulating them on their news.