The bodies of Tania Ellwood, 39, and Timothy Kerr Hamilton, 36, were discovered at Dryden Lodge on Tuesday by a maintenance worker.
Katrina Ellwood paid tribute to her sister in a Facebook post late on Thursday.
"RIP by beautiful sis," she wrote with a photo with Ellwood.
"I love you with all my heart and I'm going to miss you every single day.
"I pray you are at peace."
Two of Hamilton's nephews also paid tribute to their uncle.
"Rest in Peace Uncle Tim," Julian Rika said in a Facebook post.
"Gonna miss you and your crack-up jokes ... love you bro ... too early.
Bowen Rika said his uncle had the "biggest heart".
"Rest in peace uncle Tim. Tim had the biggest heart, so gentle and was the funniest with whanau and friends. I love you so much rest in peace."
Police said the deaths would be referred to the coroner at the end of the investigation.
The discovery of the bodies followed a police appeal to the public on Tuesday morning to help find Ellwood, saying they were concerned for her safety.
Ellwood was last seen in Newmarket about 9.30am on February 28.
She had last been in contact with family the night before at 6pm and it was said to be out of character for her not to be in contact.
Ellwood is listed on StarNow as being an actor, hair stylist, make-up artist and fashion stylist. She landed a spot on Shortland Street playing a minor character called Mandy Timmins.
However, producers for the soap opera, South Pacific Pictures, said while Ellwood was confirmed to appear as an extra on one episode in 2006, she pulled out at the last minute and the role had to be recast.
