Austin couple who share girlfriend want three parents for their children

Open marriages

An Austin couple is filing for divorce in order to include their shared girlfriend in the relationship.

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@Relationships36 Open marriages

An Austin couple is filing for divorce in order to include their shared girlfriend in the relationship.

Click through to see celebrities who are in open marriages.

@Relationships36 Image 1 of / 24 Caption Close Austin couple who share girlfriend want three parents for their children 1 / 24 Back to Gallery

A married couple with three children are filing for divorce so their shared girlfriend won't feel left out.

Cristina and Benno Kaiser have been married 12 years and are in an open relationship with 21-year-old Sierra Kuntz. By divorcing and one of them then marrying Kuntz, they plan to give her legal rights to the children.

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"Cristina and I decided this was something that needed to be done in order for Sierra to understand the depth of how much we love her and want her to be part of our family," Benno told the Daily Mail.

The couple has yet to decide who will marry Kuntz, a move the pair believes will show Kuntz the tri-relationship is not "temporary thing."

The Austin couple met Kuntz at a pet store, and after several dates began to strengthen what they call their "tri-lationship."

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While 31-year-old Christina and 37-year-old Benno are at work, Kuntz is the main caregiver to the three children, ages six, seven and 11.

"This lifestyle isn't for everyone," said Benno. "There are a lot of people that are monogamous and are happy with just being with one person and that's completely fine. Every one of us is different. But before you judge, take a look at our lives and see the benefit of it. I couldn't imagine my life any other way."