Trump Jr. and O'Day allegedly began a months-long affair after meeting on the set of Celebrity Apprentice in late 2011. After his wife Vanessa discovered the messages exchanged between the pair, insiders say she tried to shame O'Day into calling things off.
"She called Aubrey with her kids on the phone," a source told Us Weekly, claiming that she hoped O'Day would feel remorseful for interrupting the family. "Vanessa went crazy and was super jealous."
At the time of the alleged conversation, Vanessa shared three children with Trump Jr.: daughter Kai, now 10, and sons Donald III, now 9, and Tristan, 6. They have since welcomed son Spenser, 5, and daughter Chloe, 3.
Trump Jr. and Vanessa announced their plans to divorce on March 15 after 12 years of marriage, with several sources citing the pressures of being in the presidential family as the reason for their split. But following the split, insiders revealed that the couple held on to the secret of Trump Jr.'s affair about six years prior.
"When it started, he and Aubrey were very serious all of a sudden," a source close to the Danity Kane singer said. "He told her it was over with his wife, that they were separated and he didn't love her — all of that stuff."
O'Day, now 34, believed him, the insider said.
"Aubrey fell for him hard. She thought they were going to be together for real," the source claimed.
The source revealed that the romance between Trump Jr. and O'Day began to heat up toward the end of taping for season 5 of Celebrity Apprentice, on which she was a contestant and he was an adviser.
Another confidant said that Trump Jr. was serious about his relationship with the singer, claiming "he fell in love with her" and told was he wanted to leave Vanessa to be with her.
Ultimately, their romance ended after Vanessa learned of the affair and his family, including now-President Donald Trump, told him to "knock off" his fling with O'Day.
"They pressured him to end it with Aubrey," the source said.
When Trump became president in 2016, O'Day tweeted a series of cryptic messages about having a "story" that could wreck the family's image.
"I'm embarrassed to be an American," the singer wrote in a of now-deleted tweet following President Trump's election.
When a follower pointed out that she had appeared on his NBC reality show, she replied, "No. My story I didn't tell is worth millions now… This doesn't hurt me, it hurts America."
In another tweet, she added, "I don't have a nondisclosure and Trump is lucky I haven't said what I know. He is garbage."
O'Day has not spoken out about reports detailing her alleged affair with the First Son, nor have Trump Jr. or Vanessa.
The couple met at a New York City fashion show in 2003 and were married in November 2005. They announced on March 15 in a joint statement that they planned to follow through with a divorce.
"After 12 years of marriage, we have decided to go our separate ways," the couple said in a joint statement to media.3comments
"We will always have tremendous respect for each other and our families. We have five beautiful children together and they remain our top priority. We ask for your privacy during this time," they continued.
Vanessa filed for divorce on Thursday afternoon in Manhattan Supreme Court. She filed an "uncontested proceeding," meaning she did not expect a battle over the couple's assets or for custody of their five children.