Priebus also suggested that Trump would pivot into general election mode but that it might take some time, remarking that in private, the candidate is "far more gracious and personable than I think you see at rallies."...ADDED: The quote in the post title is talking about Trump as if he's a child.
[Priebus] rejected the notion that Trump's campaign would assume a firm grip over the convention process, saying people on the candidate's team have shown "no indication" of seeking control of the party.... "It's the party's party."
May 6, 2016
"He’s trying, and honestly, he’s trying and I will tell you what, I honestly think he understands that building and unifying and growing the party is the only way we’re going to win. And I think he gets that."
Said Reince Priebus.