SPRING VALLEY, N.Y. (CBSNewYork/AP) — The biological father of the only child who managed to escape from the sinking van that killed his mother and three siblings in the Hudson River shared his pain Wednesday.

CBS 2’s Sean Hennessey spoke with La’Shaun Armstrong’s father, Todd Johnson, who marveled over how his son was able to stay alive.

“I’m so proud of my son and his ability to face danger as bravely as he has,” Johnson said from prison, where he was incarcerated following a robbery conviction.

Lashanda Armstrong loaded her children into the van eight days ago and drove down a boat ramp into the river in Newburgh. Police said Armstrong had been involved in a domestic incident with her boyfriend Jean Pierre at her apartment minutes earlier, and her friends say she was distraught that day.

Pierre, the father of the other three children who died along with their mother, also spoke out Wednesday and said he was not directly responsible for the tragedy, but wishes he could change parts of his past.

Pierre doesn’t face any charges.

“I have been inaccurately portrayed as being directly responsible for the tragedy,” Pierre said in a prepared statement released through a lawyer. “If I could, I would have changed some things in my past.”

Armstrong died with 5-year-old Landen Pierre, 2-year-old Lance Pierre and 11-month-old Laianna Pierre. Ten-year-old La’Shaun survived by climbing through a window of the sinking minivan.

“He’s an extraordinarily remarkable person, and uplifting, and a gift from God,” Johnson said.

A woman who was driving past the boat ramp April 12 saw La’Shaun waving his arms. The woman, Meave Ryan, said La’Shaun told her that his mother had had a “big, big argument about my stepdad’s cheating on her” before piling the four children into the van and speeding into the river.

Ryan took La’Shaun to a nearby fire station. Rescuers immediately went to the river, but it was too late: They found the van about 25 yards from shore in 8 feet of water, and everyone inside was dead.

Few will ever know what was going on in the mind of Armstrong. Pierre’s apparent womanizing may have added to her stresses of children, a job, school and finances.

“I felt like she was in a situation where she couldn’t find a rational way to get out,” Johnson said.

Family members sang “Happy Birthday” for the youngest victim, Laianna, at the river landing on Wednesday, marking her first birthday.

A funeral for the mother and the three children had been planned in Spring Valley in Rockland County for Thursday. But Pierre said he wants to grieve for his children privately. After consulting with the Armstrong family, he said, the funeral for his children will be Monday, separate from their mother’s funeral.

Pierre’s attorney, Stephen J. Powers, said his client is devastated and is staying with relatives. Powers said Pierre would not attend Lashanda Armstrong’s funeral because he did not want to be a distraction.

Pierre will spend the day preparing for Monday’s funeral for his children.

“I loved Landen, Lance, Laianna, Lashanda and still love La’Shaun with all my heart,” Pierre said, “and am shocked and distraught by what happened.”

Powers said earlier reports that a judge had ordered Pierre to stay away from his children were incorrect. He said it is his understanding that a charge of endangerment against Pierre stemming from when a 2-year-old boy was found wandering the streets in February was adjourned in contemplation of dismissal. That means if Pierre stays out of trouble for a certain period, the charge will be dropped.

Court offices in Newburgh were closed by 4:30 Wednesday afternoon, and that information could not be confirmed.

(TM and Copyright 2011 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2011 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)

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