NEW ULM, Minn. — An arrest warrant was issued today for Colleen Hauser, who failed to bring her 13-year-old son, Daniel, to a court hearing on whether he should receive chemotherapy against his wishes.

The mother and son have been missing since Monday evening, after they went to a medical appointment that suggested Daniel’s cancer is getting worse.

Only the father, Anthony, was in court today. He said he didn’t know their whereabouts, nor had he read the judge’s order requiring him to get treatment for Daniel or lose custody of the boy.

The attorneys in the case and Brown County District Judge John Rodenberg attempted to locate the missing Hausers during the hearing by calling Colleen’s cell phone, her mother and Daniel’s family doctor. They also questioned Daniel’s 16-year-old sister on the stand.

“The court’s primary objective at this point,” Rodenberg said during the hearing, “is to get to Daniel Hauser.”

Anthony testified that he had last seen his wife leaving their Sleepy Eye farm on Monday evening. He said his wife only told him “she was going to leave” and “that’s all you need to know.”

Rodenberg ruled last week that Daniel must receive chemotherapy for his cancer, a former of Hodgkin’s lymphoma, even though it is against the family’s spiritual beliefs and wishes. The Hausers belong to the Nemenhah, a quasi-American Indian group that favors natural remedies and opposes any medicine that attacks or harms the body.

The Hausers had been ordered to come to court today with X-ray results showing whether Daniel’s cancer had gotten worse. The Hausers were also supposed to select a pediatric oncologist to treat Daniel.

Testifying by phone at the hearing, Dr. James Joyce said he examined Daniel on Monday and found that the 13-year-old was suffering chest pain and had a new lump under his right collarbone.

Joyce said he recommended that Daniel be transferred immediately for further evaluation by an oncologist and he recommended doctors from Children’s Hospitals and Clinics of Minnesota, the University of Minnesota and the Mayo Clinic.

Instead, he testified, Daniel and his mother left in a hurry along with a woman who was advising them. Much of today’s hearing focused on the apparent influence of this mystery woman, Susan Daya (also known as Susan Hamwi), who apparently is an attorney from California but isn’t formally representing the Hausers in the case.

“With Susan Daya’s urging” at the examination, Joyce testified, “they indicated they had other places to go and didn’t want any (oncologist) referrals right now.”

A key question for attorneys in the case has been whether Daniel is refusing chemotherapy on his own, or whether his parents have been influencing his judgment.

The next question may be who is influencing the parents.

Attorneys on both sides were stunned by the disappearance. Daniel’s court-appointed attorney, Philip Elbert, said he was angry that the parents didn’t bring his client to court. During the trial over whether Daniel should be forced into chemotherapy, Elbert argued that the judge should listen to the Hausers and allow them to treat Daniel with alternatives, including vitamins, herbs and ionized water. Now that the judge has ruled, he said it is unfortunate that Colleen Hauser has chosen not to listen to him.

“The resolution,” he said, “is not to flee.”

Brown County Attorney James Olson called Colleen Hauser’s actions “absolutely crazy.” The warrant was issued so that police nationwide can apprehend her. While she could be arrested for failing to appear in court or violating a court order, Olson said the goal of the warrant is to find Daniel rather than to punish the mother.

She “holds the keys to the jail,” Olson said. If Daniel is found, the judge ordered that he be placed in foster care and receive immediate evaluation by a cancer specialist.

During the trial, doctors testified that Daniel had as much as a 90 percent chance of survival with the treatment and a 95 percent chance of death without it. Daniel received one of seven recommended rounds of chemotherapy after his cancer was diagnosed in January, but didn’t show up for the rest.

Joyce’s testimony and medical records at today’s hearing suggested the initial chemotherapy had reduced the size of the tumors in Daniel’s body. However, the latest X-ray results showed “significant worsening.” Joyce also said that Daniel has extreme chest pain, probably due to a growing tumor that is pushing a catheter in his body out of place.

Rodenberg’s order regarding the chemotherapy was conditional on Daniel still being able to benefit from the treatment after the months of delays. Joyce said the mere X-ray isn’t enough to determine whether the existing plan of chemotherapy and radiation will still work. He said a cancer specialist needs to evaluate him quickly.

The attorney for the Hauser parents, Calvin Johnson, said the father had been ready to send Daniel to a doctor at the University of Minnesota for further testing.

Anthony Hauser repeatedly stated “I don’t know” when asked about the location of Colleen and Daniel, and about Daya’s role.

Olson, the county attorney, said he didn’t believe that Anthony Hauser was so forgetful. The Hausers are a tight-knit family, he said, and unlikely to lose track of one another.

“Maybe I’m getting kind of cynical at my old age,” he said, “but I find that hard to believe.”

Jeremy Olson can be reached at 651-228-5583.