By Mai Martinez

(CBS) — This holiday season, a suburban woman doesn’t have to worry about what she’ll give her twin sister.

That’s because Kristen Maurer already gave her twin, Kelly McCarthy, a very special gift: a piece of herself, literally.

Identical twins Kristen and Kelly have shared a special connection since birth.

And these days, that connection is even stronger after the two battled breast cancer together.

Kelly was diagnosed first.

“It was unreal. I was like, ‘It couldn’t be. I’m 32. I’m pregnant,’” she says.

Then, a few months later, Kristen was diagnosed.

“I was more angry and upset when she was diagnosed and, likewise, when I was diagnosed, she was just very mad,” Kristen says.

Both had double mastectomies, but Kelly’s cancer required chemo and radiation, leaving her without enough tissue for a complete reconstruction.

But the twins’ doctor had an idea.

“He thought it might be a good idea to transplant some of my skin and tissue to rebuild her breasts. Since she’s slender, she didn’t have enough to do both,” Kristen says.

An unexpected pregnancy delayed the surgery.

The surgery took place Nov. 12 and was such a success the twins are already joking about it.

Jokes aside, both realize how very special their bond is.

“It’s kind of nice to have a piece of her with me at all times. It is neat,” Kelly says.

Both twins are in the clear now.

If you’re wondering how rare this type of surgery is, the twins say they were told they are the fourth set of twins to undergo this type of surgery, but the first set in which both twins had breast cancer.