(CNN) Rep. Joe Kennedy III will endorse fellow Massachusetts Democrat Sen. Elizabeth Warren for president on Saturday, when she is expected to officially launch her 2020 campaign.

According to multiple sources familiar with the plans, Kennedy -- a former student of Warren's -- will introduce Warren and in part discuss why he believes Warren's record on economic issues will set her apart from the rest of the field from Lawrence, Massachusetts. The Kennedy endorsement news was first reported by the Boston Globe.

Other members of the Massachusetts delegation will also speak at the rally, including Sen. Ed Markey and Rep. Lori Trahan, as well as Lawrence Mayor Dan Rivera and Boston City Councilwoman Michelle Wu, those sources said. All are expected to indicate their official support for Warren's presidential campaign.

Warren will be joined by family, including her husband, Bruce, and her two children. Some of her grandkids are also expected to be in attendance.

Warren has been teasing the announcement of a presidential bid, and was the first major Democrat to announce an exploratory run, on New Year's Eve. Since then, the senator has traveled to the early primary states of Iowa, New Hampshire and South Carolina, and last month visited Puerto Rico, using the trip to slam President Donald Trump's handling of Hurricane Maria recovery efforts as well as his insistence on building a wall along the US southern border.

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