Hewlett Packard Enterprise hpe chief executive Meg Whitman will co-host a campaign event for Democratic presidential nominee Hillary Clinton on Wednesday in Silicon Valley.

Clinton herself, who was diagnosed with pneumonia two weeks ago, will not make it. But her running mate, Virginia Senator Tim Kaine will be there.

Whitman, a lifelong Republican who had backed New Jersey Governor Chris Christie in the primaries, subsequently rejected the Republican nominee, Donald Trump, and said she will vote for, support, and raise money for Clinton instead.

“On events, I do what the campaign asks me to do if I can fit it into my business schedule,” Whitman said in an interview with Fortune on Tuesday night.

Her public debut stumping for the Clinton campaign occurred last month in Denver, and Whitman said it was because she already was going to be in the area.

Wednesday’s lunch will be at the Atherton, Calif. home of philanthropist Jill Manus.

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Wednesday will be a busy day for Kaine. In the morning, he’ll attend a roundtable hosted by Democratic National Committee backer Steve Spinner, then the Whitman-Manus lunch, followed by an early evening fundraiser co-hosted by tech entrepreneurs Mark and Ali Pincus.

For more on Whitman and Clinton, watch:

On Tuesday, reports surfaced that another prominent Republican, former president George H.W. Bush, also plans to vote for Clinton.