1950's childrens books

[garybfsl]

I am trying to remember books I read as a child in the 1950's in England. Does anyone remember a plot (part of a series) which involved a group of children, a father, a motor boat and the line from the father to one of the children "Do you want to know a secret" to which the reply was "If you tell me it will not be a secret" so he never told him.

Ring any vague bells?

[carrot99]

Don't remember the quote, but was it the Swallows and Amazons series? A group of kids messing about in boats. Camping on an island and pretending to be pirates against another group of kids. They had various adventures and I think there was a father around.