Hi,
This is not my family research but I ran across a photo that I thought might be of interest to anyone who might be researching Lili Boulanger.
Here is a link for it, I hope it works, if not
http://lcweb2.loc.gov/cgi-bin/query/D?ils:54:./temp/~pp_vrka::

It's in this collection.
General information about the Bain Collection is available at http://hdl.loc.gov/loc.pnp/pp.ggbain

This might be the research number.
ggb2006003365
I hope it helps someone out,
Cathy