The angry confrontation started around 6:30 p.m. Tuesday when Jean Pierre, in an apparent violation of a restraining order, arrived at the Newburgh, N.Y., apartment of Lashanda Armstrong, neighbor Latoya James told the New York Daily News.
"The dad was banging on the door real loud," James said Friday. "He called to her, 'Open the (expletive) door!' He was there about a half an hour -- he was on the phone as well."
James said the dispute ended with a tender moment between Jean Pierre and 10-year-old Lashaun Armstrong, the lone survivor when his mother drowned herself and his three siblings in the Hudson River.
"He came down and opened the door ... He said, 'Daddy, I love you,'" James, 30, said. "He said, 'I love you too, man,' and kissed him on the forehead."
About 15 minutes later James watched Lashanda Armstrong put her four children into the van and drive off, a short ride that ended with all but Lashaun drowned inside the vehicle.
The relationship between Armstrong and Pierre was often combative with many fights about his infidelities, neighbors said.
Pierre was released Wednesday night after questioning by police and was unlikely to face charges, the Daily News reported.
Theater accidentally screens 'Nymphomaniac' trailer instead of Disney's 'Frozen'
Caroline Berg Eriksen: Soccer player's wife triggers debate with post-birth selfie