Former first lady Michelle Obama will speak at the DNC in Chicago this week, ABC News has confirmed with her office.

Her appearance, first reported by Essence Magazine, will be among a lineup of prominent Democratic leaders who are rallying in support of Vice President Kamala Harris and Minnesota Gov. Tim Walz.

Former President Barack Obama is also scheduled to speak at the DNC.

According to a source familiar with the planning, Michelle Obama will speak on Tuesday -- the same day as the former president.

-ABC News' Michelle Stoddart and Gabriella Abdul-Hakim

Former Democratic Rep. Tulsi Gabbard will assist Trump in preparing for his first debate against Vice President Kamala Harris.

"[Trump] does not need traditional debate prep but will continue to meet with respected policy advisors and effective communicators like Tulsi Gabbard, who successfully dominated Kamala Harris on the debate stage," Trump campaign National Press Secretary Karoline Leavitt wrote in a statement to ABC News, confirming a development first reported by The New York Times.

Gabbard, a former Democratic congresswoman from Hawaii and a one-time Democratic presidential candidate during the 2020 election, gained brief momentum during her presidential run after challenging Harris on the debate stage on topics like criminal prosecutions.

Since leaving the Democratic Party, Gabbard has been gaining traction among Trump supporters, and more recently she has appeared on Fox and other conservative news outlets attacking Harris.

– ABC News’ Rachel Scott, Soo Rin Kim, Kelsey Walsh, and Lalee Ibssa

The first debate between Vice President Harris and former President Trump will be held by ABC News at the National Constitution Center in Philadelphia.

The Sept. 10 debate will be moderated by ABC News anchors David Muir and Linsey Davis.

It will air live at 9:00 p.m. ET on the network and on its 24/7 streaming network ABC News Live, Disney+ and Hulu.

Prime-time convention programming will air live from the United Center in Chicago from 6:30-11 p.m. ET on Monday and 7-11 p.m. ET on Tuesday through Thursday.

Beyond the nominee acceptance speeches --vice presidential nominee Tim Walz on Wednesday and presidential nominee Kamala Harris on Thursday -- programming has not been finalized or announced yet.

It has been confirmed, however, that "current and past Presidents are expected to participate in convention programming." President Joe Biden, Former President Barack Obama and Bill and Hillary Clinton are all tentatively slated to speak at the convention, sources familiar have told ABC News.

Much of the rest of the schedule will be rolled out in the coming days.

High-profile political leaders are also expected to make remarks at the DNC's Constituency Caucuses and Councils meetings that will take place throughout the week. Celebrities are also expected throughout the week, with a number of big names announced already to participate in events adjacent to the convention, including John Legend, Jon Stewart, Billy Porter, Joan Jett, Octavia Spencer, DJ D-Nice and Lil Jon.

-ABC News' Isabella Murray and Brittany Shepherd