As SpaceX was poised to hit the Nasdaq following the largest IPO on record, Elon Musk's second-in-command, Gwynne Shotwell, didn't dismiss the possibility of an eventual tie-up with Tesla , Musk's other trillion-dollar company. Speaking to CNBC's Morgan Brennan on Friday, Shotwell said such a combination "might make Elon's life a little easier." Musk officially became the world's first trillionaire due to his stakes in the two companies. At SpaceX, he has hefty control over decision making,