Yes, Rudy’s daughter has endorsed Harris/Walz in an editorial published in Vanity Fair. In her piece, she explains:
Americans of just how calamitous being associated with Trump can be, even for those who are convinced he’s on their side. Watching my dad’s life crumble since he joined forces with Trump has been extraordinarily painful, both on a personal level and because his demise feels linked to a dark force that threatens to once again consume America. Not to disregard individual accountability in the slightest, but it would be naive for us to ignore the fact that many of those closest to Trump have descended into catastrophic downward spirals. If we let Trump back into the driver’s seat this fall, our country will be no exception.
She goes on to write:
Trump being the president was the worst thing that ever happened to my dad, to my family, and to our nation’s modern history. The consequences will only be more severe—and irreversible— a second time around. Thanks to the extremist Supreme Court he stacked, Trump would take office with full immunity: no checks on his power whatsoever. If the president isn’t going to be subject to the law like every other citizen, which remains incomprehensible to me, then our president had better have a moral compass.
Really, her whole, heartfelt piece is worth a read: Caroline Giuliani's Endorsement.