Anna and Lucy DeCinque, 35, will be marrying 37-year-old electrician Ben Byrnes, who they have both been dating since 2011.
The trio, from Perth, became engaged on the latest episode of Extreme Sisters, a series that explored “the most obsessive and inseparable sibling relationships”.
Byrnes popped the question during a romantic park picnic with the twins and presented them both with a set of three bands each. The middle ring for both women featured huge round diamonds.
Byrnes said the three bands symbolised the three of them, adding: “Anna, you mean the world to me and I want to spend my life with you, and Lucy, you mean the world to me and I want to spend my life with you too. I love you, I love you both.”
Polygamy is not legally recognised in Australia, but the twins suggested they may be able to get married in “Malaysia, Indonesia or parts of America”.
In Malaysia, polygamy is banned for non-Muslims, but legal for everyone in Indonesia. The act is illegal in all 50 states of the United States and punishable by a fine, imprisonment or both.
Byrnes promised his fiancees he was “willing to do whatever it takes to make you happy”.
Anna and Lucy also said they wanted to be pregnant at the same time and would plan to do so through IVF, which they have been wanting to do for years.
In a clip posted to their Instagram the pair are seen taking pregnancy tests together. But they both come back negative.
Anna said if she became pregnant, Lucy “would definitely get pregnant straight away because our bodies need to be the same”, and added: “We would try to make that happen, definitely.”
The sisters previously spoke of their plans to become pregnant at the same time on Australia’s Today show in 2019.
They admitted it could be difficult trying to have joint pregnancies, and said there would be “a lot of pressure on Ben”.
They said: “Love is love, we are all adults. Our mum’s actually convincing us to give birth naturally. I don’t know how that’s going to work.”
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