There is a little debate going on in Puzzling StackExchange on this post: A river crossing puzzle
The issue is with this sentence:
Billie shouts: "They're also pretty small. I will only go with Devin alone."
Does Billie mean that he will only go if Devin is with him (as in he won't go alone), or does it mean that he will only go with Devin and but can also go alone?
I think it's the latter; Billie merely stated who he would and wouldn't go with, not whether or not he would go alone.