Only a portion of the photographs collected by Gillis were used in the publication Growing Up in Old Lithuanian Town. The photographs and photograph envelopes in the collection provide visual and documentary information that was not included in the final publication.

The photographs collected by Gillis include an illustration of Vytautas the Great, from as early as 1392-1430. However, most of the images illlustrate Grand Rapids Lithuanians from around 1880 at the earliest to as late as 1996.

To date, the Library has not received Mr. Gillis' manuscript notes used in the development of the book. The manuscript materials that are included in the collection are the documents associated with the editing and publication process, done via City Historian Gordon Olson and the Grand Rapids Historical Commission.