In Chapter 27 of Rilla of Ingleside, Rilla describes her writing desk:

“Oh, what is happening on the western front tonight as I write this, sitting here in my room with my journal before me? Jims is asleep in his crib and the wind is wailing around the window; over my desk hangs Walter’s picture, looking at me with his beautiful deep eyes; the Mona Lisa he gave me the last Christmas he was home hangs on one side of it, and on the other a framed copy of “The Piper.” It seems to me that I can hear Walter’s voice repeating it–that little poem into which he put his soul, and which will therefore live for ever, carrying Walter’s name on through the future of our land. Everything about me is calm and peaceful and ‘homey.’ Walter seems very near me–if I could just sweep aside the thin wavering little veil that hangs between, I could see him–just as he saw the Pied Piper the night before Courcelette.

In Chapter 9 of Emily’s Quest, Emily and Dean decorate in the Disappointed House

They hung their pictures one day. Emily brought her favourites up, including the Lady Giovanna and Mona Lisa. These two were hung in the corner between the windows.

“Where your writing-desk will be,” said Dean. “And Mona Lisa will whisper to you the ageless secret of her smile and you shall put it in a story.”