“In the first movie, they [Jacob & Newt] made such an impression on each other; it’s like you’re connected forever after you go through something like that. And Newt trusted Jacob enough to bring him along, to introduce him to all the creatures – I mean, that’s huge. And then Newt did the ultimate kindness by basically helping Jacob buy his bakery. That’s more than friendship. That’s like a brotherhood. And so in the second movie, when they met up again, it was just like old times. It was instantly back into the adventure, back into the fun. And that’s what it is for this movie. You see them meet on the train and it’s right back into it again. They have a shorthand that only comes with true friendship.”
Source: Bearpost