A makeshift memorial at the scene of the Hudson River tragedy. Brian Branch Price for News
"He needs time," said his grandfather who would only give his name as Larry. "Right now, we're gonna take care of him."
On the night of the tragedy, Lashaun pleaded with his mother to change her mind as she drove the family van down a boat ramp into the brackish water.
"Mommy, Mommy what are you doing?" Lashaun screamed.
Seconds later, he was swimming for his life after escaping from the doomed vehicle. By the time he reached the shore, the van had disappeared with his mother and three younger siblings inside, according to a good Samaritan who found the shivering boy.
While Lashaun told his rescuer his mother drove silently to the river, Armstrong posted a macabre Facebook apology just 30 minutes before the murder-suicide.
"I'm so sorry everyone forgive me please for what I'm gonna do.... This Is It!!!!" she wrote from her BlackBerry at 7:13 p.m.
The message was reported on MidHudsonNews.com after the website gained access to the dead woman's Facebook page.
The mother picked up her four children from day care about six hours earlier than usual on Tuesday morning.
"It did seem a little strange at first, but she said her work scheduled would vary so we didn't make much of it," said owner Watson.
Hours after their 11:30 a.m. departure, Watson was stunned to learn of their 8 p.m. deaths.
"I haven't processed what has happened yet," she said Thursday. "The kids ask me if if the children are coming back ... How do you explain what happened?"
Armstrong drowned along with Landon, 5, Lance, 2, and 11-month-old Lainaina.
"He was blaming himself for not teaching them how to swim and for not unbuckling his little sister," said Meave Ryan, the good Samaritan who Lashaun flagged down.
"It's not your fault, Lashaun. You're courageous."
The funerals are scheduled for April 21 in Spring Valley, N.Y.