Chapterbib gives 'citation undefined' and all [?]

This is my first time posting. I have been struggling to include reference lists after each chapter included in my main .tex file. Though the .bbl file includes all the references, all the citations appear as [?] and no reference list is produced. I have run pdflatex, bibtex, pdflatex, pdflatex. I have tried using one .bib file and creating separate ones for each chapter. I know the .bib file is fine, because I initially had all the writing in the main file, but hadn't put in all the chapters and it compiled fine. When I added the second chapter I realized I needed to use \include{chap} to get separate lists.

Here is an example of my main file:

\documentclass[12pt]{report}

\usepackage[top=1in, bottom=1.25in, left=1.25in, right=1.25in]{geometry}
\usepackage{titlesec}

\titleformat{\chapter}{\singlespacing\normalfont\LARGE\bfseries}{\thechapter.}{16pt}{\LARGE}
\titleformat{\section}{\singlespacing\normalfont\Large\bfseries}{\thesection}{12pt}{\Large}
\titleformat{\subsection}{\singlespacing\bfseries}{\thesubsection}{12pt}{\Large}
\titleformat{\subsubsection}{\singlespacing\bfseries}{\thesubsubsection}{12pt}{}
\titlespacing*{\chapter}{0pt}{-19pt}{0pt}

\usepackage[round]{natbib}
\usepackage{chapterbib}

\usepackage{setspace}
\usepackage{url}
\usepackage{textcomp}
\usepackage{amsmath}

\begin{document}
\tableofcontents

\include{chap1}
\include{chap2}

\end{document}

Here is an example of a chapter (the others are similar):

\chapter{Surface Energy Balance}
\label{else}
\doublespacing

Text \citet{Paterson10}.

\singlespacing
\bibliographystyle{plainnat}
\bibliography{bib1}

And the .bib entry:

@book{Paterson10,
Author = {K. M. Cuffey and W. S. B. Paterson},