NEW YORK (AP) – Formerly conjoined twins Carl and Clarence Aguirre have begun wearing custom-built plastic helmets so that the rebuilding of their skulls can be postponed and they can stay in therapy designed to get them walking and talking, doctors said Friday.

Staying out of the operating room is “a luxury they’ve earned” by responding so well to the series of major operations that climaxed with their separation last August, said Dr. David Staffenberg, chief of plastic surgery at the Children’s Hospital at Montefiore Medical Center in the Bronx.

“They’re just soaking everything up,” he said. “They’re gaining by the day. The benefits of therapy outweigh the benefits of any of the reconstructive surgeries.”

The 3-year-old boys from the Philippines are taking steps with the aid of little walkers and could be toddling on their own “in a month or two,” said Dr. Robert Marion, their pediatrician, at a news conference at Montefiore.

There’s been much less progress in their speech, however, and Marion said, “We don’t really understand why.” Doctors did find some blockage in the boys’ ears and have inserted tiny tubes there, a common procedure to relieve pressure and fight infection, in hopes that better hearing might make for better speech.

“They know what people are saying, and they understand,” Marion added. “They really are cognitively OK.” The boys manage a few words, including “hi,” “bye” and “thank you,” doctors say.

Dr. James Goodrich, the neurosurgeon who led the separation operation, said the slow start “isn’t surprising if you consider that they spent 18 months in social isolation in the Philippines, then came to the U.S. and an entirely different language.” In addition, he said, the boys were often sick, “and when you’re sick you don’t learn”; had blocked, infected ears; and apparently were “hard-wired together” by the bit of brain they shared and could probably communicate in some form without speaking.

The new white helmets, made of polypropylene on the outside and foam padding on the inside, replaced the twins’ heavy bandages on Thursday and “didn’t seem to bother them at all,” Marion said. They are meant to protect the tops of the boys’ heads, where they were once attached and which are now covered only by leathery layers of skin, from normal 3-year-old activity – like the fight he witnessed a few days ago.

Marion said he saw the brothers “going at each other” when they were in the same crib.

“They were fighting, grabbing, pushing each other into the bars. They were fine, but it was clear that if we’re not going to reconstruct the skulls, they’ll need more protection.”

When the boys eventually do undergo skull reconstruction – Goodrich said that might happen in the fall – it won’t be quite as big as job as anticipated, Staffenberg said. A few square inches of bone has regenerated on its own in both skulls, he said, a surprising development in children as old as 3.