How many books has Colin Forbes written with Tweed as the main character?

There seems to be some confusion. There is no known author named Colin Forbes with a series featuring a character named Tweed.

It is possible that:

* You are mistaken about the author's name or the character's name.

* The books are not widely known or published.

* You are thinking of a different author and character.

Could you please provide more information, like the genre of the books or any specific titles? This would help me find the correct information.