DeAnna Rivas begged her husband Manny to take on a shared girlfriend to fulfill her sexual desires.
Now DeAnna, 27, and Manny, 28, are engaged to 20-year-old Melissa James.
The trio share a king-size bed and all three plan to marry in the future – although this is not legal in their home state of Florida, US.
DeAnna said: “There are lots of benefits on the physical side – it is very adventurous.
“Sexually it is very interesting. We open up our marriage and our bedroom. We do everything.
“We all sleep together as a threesome and sometimes we will pair off.
“It helps with childcare because one of us can watch the kids while the other two have fun.”
Now Melissa, known as MJ, takes care of the couple’s children, Vaneza, seven, and Gabriel, four, while DeAnna and Manny work.
DeAnna, a shop assistant, said: “Before we found MJ I was so miserable, I felt like there was a hole in my life that only another woman could fill.
“It took me four years to convince Manny but now we have MJ in our lives and the children love having two mums – we couldn’t be happier.”