SALT LAKE CITY, Utah (AP) -- A day after the 26-hour surgery that separated their 4-year-old conjoined daughters, Jake and Erin Herrin said they were overwhelmed by their reunion with Kendra and Maliyah.

"It was like seeing them born again. They were in brand new bodies," Jake Herrin said. "It was really an amazing experience."

But they were also a bit confused. Since birth Kendra has been the twin on the left when the girls were facing their parents, Maliyah on the right.

But now, cradled in sand-filled hospital beds at Primary Children's Medical Center that reduce pressure on their skin, the girls were reversed.

"That was a little shocking," Erin Herrin said during a news conference at the hospital Wednesday.

The twins are in critical condition, as expected after major surgery, but their vital signs have remained stable and they show no early signs of dangerous post-surgery infections, doctors said.

"They are doing extremely well," said Dr. Rebecka Meyers, coordinator of the separation, which began Monday morning and concluded Tuesday.

The twins' parents said nurses have told them the girls' vital signs continue to mirror each other, as if they are still conjoined.

Kendra and Maliyah were joined at mid-torso, with some shared organs and just two legs. Doctors divided the twins' shared liver, bladder and a portion of their large intestines, and split and reconstructed their single pelvis.

Each girl kept one leg, and Kendra got their shared kidney. Maliyah was to begin kidney dialysis in preparation for receiving a kidney from her mother in three to six months.

Doctors will now determine when to wean them off pain medications and breathing machines. The girls were expected to remain in intensive care for at least a week, followed by a month in the hospital before doctors consider sending them home.

Nurses twisted the girls' sandy-blond hair into french braids, fastening them with ribbons in the twins' favorite colors -- purple for Kendra and yellow for Maliyah.

"They looked so pretty this morning," Meyers said.

The girls are thought to be the first twins with a shared kidney to be successfully separated.

In most instances, conjoined twins undergo separation between ages 6 and 12 months, but the Herrins' shared kidney forced a delay.

Doctors expect the girls will need reconstructive surgeries to help fit them for prosthetic legs.

"These girls will never be girls who did not undergo a major separation and have special battles and special needs," Meyers said. "But they will be able to live very good, fulfilling lives."

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