It’s over three and a half years since Apple’s cofounder and CEO Steve Jobs succumbed to pancreatic cancer and left this world but you may be surprised to know that Tim Cook, who succeeded Jobs as the next Apple CEO kept his contact number long after he passed away in October 2011.

The above information has been revealed in the book “Becoming Steve Jobs: The Evolution of a Reckless Upstart into a Visionary Leader” that has been released recently across digital as well as brick and mortar stores. The book also reveals many other interesting tidbits and anecdotes about Jobs. Brent Schlender and Rick Tetzeli, joint authors of the said book interviewed his wife Laurene Powell Jobs, Tim Cook, designer Jony Ive and several of his other former colleagues and friends. The book gives an insight into the life of one of the world’s top tech visionaries.

Business Insider tells about one incident narrated near the end of the book where Jobs’ close friend and Pixar’s chief creative officer John Lasseter tells about a conversation he had with Tim Cook during Laurene Powell’s 50th birthday party in November 2013.

“I got there kinda early, and Tim came in,” Lasseter said. “He came over and we started talking, and I said, ‘Do you miss him? I really miss Steve.’ And I showed him this.”

Lasseter took out his phone and showed Steve Jobs’ phone number and photo stored in favorite contacts on his iPhone saying, “I can’t get rid of that.”

On seeing this, Tim Cook also opened his iphone and showed Lasseter that he too still had Jobs’ contact number saved in his phone.

Lasseter was a close friend of Jobs and remained so up to his death. Tim Cook was close too and had even offered a part of his liver to Jobs.

“It’s funny, there’s a little club, I guess is the best way to describe it,” Lasseter says in the book. “The people like Jony and Tim, myself, that were very close to Steve up until the very end. And no one gets it, how much we miss him.”