Playing together in the Player's Turn

Couple things came up in our Mouse Guard game last night. We did a quick cursory glance through the book and didn’t see an answer, so we moved on.

Are there rules for mice doing things together during the Player’s Turn? If Player A spent a check to do something can other players help? Do they have to spend a check to be a part of the test?

Can another player (essentially) butt in to what someone else is doing? Example: my mouse was running off to do something pretty fool-hardy and another player had a Belief about keeping everyone on the team safe, so he wanted a way to try and stop me.

Nothing in the Players’ Turn supersedes the Teamwork rules on page 93-95.

Sure, why not? Players’ Turn, page 72-77, particularly Playing Nice and Negotiating on page 75. Also, Versus Tests, page 88.