The "Shark Tank" cast is heartbroken over Mark Cuban's decision to leave the hit business and entrepreneurship reality series. "Like losing a brother, it's terrible. I know I'll get over it; I hope I'll get over it,

As Vice President Kamala Harris is blitzing battleground state Wisconsin Thursday, billionaire businessman Mark Cuban is campaigning along with her.

In PEOPLE's exclusive look at 'Who's Talking to Chris Wallace?', the 'Shark Tank' investor is brought to tears while reflecting on his heartwarming friendship with Cuban — even though people "pit us a