Even if he was in clothes from the 20's . i still like this shot.. Keep it around for when he's in his 40's and can look back on it..
A friend of mine is a photographer, she took her 4 year old nephew out on a shoot in some bib overalls, she got a cute pic of him waterin a tree (no, nothing graphic) it was a clean angle, did it in b&w. It was a definate spur of the moment shot..
Take your image convert to Grayscale. Then convert back to CMYK or RGB. Make a new layer above your background layer and fill the entire layer with a redish/yellowish/brownish color. Set you layer mode on your layers pallet to "color" (circled below) then drop your opacity of that layer (circled below) to reach your desired effect.
If you want more contrast try placing a curve or levels adjustment layer between the two layers. By putting it between them you are effectively altering pixel data of the background image w/o screwing up your color. This is a really flexible way to make sipia pics expecially when you print the image out becasue it may not resemble what is on your screen and you can then adjust accorningly.
The color layer mode is definately someting you should play with for a lot more than sepia pics though. It keeps the image data below but changes channels (re-mixes) them to take on the color in which you paint above. You do not have to fill an entire layer with the color either, you can paint it in selectiely to say smooth out the color of an aluminum frame or the chrome on a pipe...