An eyewitness tells ET that Rivera and Spade were joined by Adam Sandler, Rob Schneider and their families at the pool. Spade is currently on the Here Comes the Funny Tour with his fellow comedians, who are all performing on Friday at the Maui Arts and Cultural Center.
Aside from sharing a kiss, the eyewitness says Spade and Rivera were discreet. "The pair went for a short swim, hugged and had lots of body contact in the pool. They kept to one side of the pool where there was the most covering from prying eyes," the eyewitness recalls. "Outside of the pool, they sat on lounge chairs and talked animatedly. They spent about an hour poolside together.”
"They were very happy," the onlooker adds. "They looked pretty comfortable together."
The eyewitness also tells ET that the two were spotted eating at Duke's restaurant in Waikiki. "They were definitely out and about together," the eyewitness notes.
Another source tells ET that Spade and Rivera's relationship is "very casual and they had a fun time together."
"Naya was in Hawaii with a friend and met up with David," the source explains. "They have known each other for a little bit through friends."
In addition to spending time with Spade, Rivera has been sharing selfies on Instagram this week of her posing in a sexy black bikini. "Cuz why not!" she captioned one of the pics.
In July 2014, the Glee star married Dorsey in a surprise wedding, just months after calling off her engagement to rapper Big Sean. Upon filing for divorce in November, Rivera requested sole physical and legal custody of her and Dorsey's 1-year-old son, Josey, with visitation to be granted to her ex.
As for Spade, he has a daughter, Harper, with 31-year-old Playboy model Jillian Grace.
ET has reached out to Rivera and Spade's reps.
In September, Rivera spoke exclusively with ET about her memoir, Sorry Not Sorry, and at the time seemed head over heels for her husband. "I have always kept a flame for him," she admitted, referring to her feelings after their initial 2010 breakup. "In between boyfriends or whatever, if I was single for a minute, I would always answer his emails and go see him. He was just kind of always the One."
Check out more of ET's interview with the actress:
Additional reporting by Jennifer Peros and Kayley Stumpe.