Using the chicago style manuel, how would you cite this in in-text citation.

Smith doesn’t disagree. (In fact, he claims he figured this out himself!)

Citation: Smith, 2008, p. 15

There needs to be a citation after the word disagree and at the end after the parenthesis. Both are by the same author and located on the same page. I am not sure how to do this.

http://nutsandbolts.washcoll.edu/chicago.html

and

http://www.chicagomanualofstyle.org/tools_citationguide.html

What you've typed is more like APA. Here's an example from the second link above:

(Lattimore 1951, 91–92)

I'd put the identical citation at each place you see the need.

To cite this passage in Chicago style with in-text citations, you would include the author's name, the publication year, and the page number in parentheses immediately after the quote or statement. Since both citations refer to the same author and page number, you only need to include the full citation after the parentheses.

Here's how you would format it:

Smith doesn’t disagree (Smith 2008, 15).

Make sure to include the proper punctuation, such as the period at the end of the sentence, outside the parentheses.