Genealogy Challenge - Who is Carl?

I was just reading Maureen Taylor's article on crowdsourcing on the Family Tree Magazine website.  In the article she explains what crowdsourcing is and how the Library of Congress is using the technique to identify old prints and photographs.

I decided to flip through the link she provided for the Civil War Collection. I've come across a photo that I believe we genealogists should be able to solve.  Particularly those us who are strong in Civil War or Military History.

Here's what we know:

• The name of the person in the photo is Carl
• He was 18 years old when he was killed on April 1, 1865
  He was killed in combat during the fighting at Dinwiddie Court House (March 31) and Five Forks (April 1), shortly before Lee surrendered at Appomattox Court House on April 9, 1865.
• Possible identification: Carlos E. Rogers of Company K, 185th New York, who was killed on either March 29 or 30, 1865, at Quaker Road in Dinwiddie County. (Source: North South Trader's Civil War, vol. 35, 2010, p. 55)

How quickly can we identify Carl and his mother who wrote the note?  I bet we could do it pretty quickly. Anyone up for the challenge?

Here's the photo of Carl but please see the original page in case there are any more clues there: