Hey Mark,
I'm not entirely sure what treatment the kid's jersey would get. I do know that this was taken in 1913, and Matty's uniform would have had a violet trim, so judging by the value of what the kid has on, I would imagine it's probably a deep blue or something. I have a feeling I'll just be doing some research on children's jersey's from that era to have a better idea...lord knows I can't wing it!!
Graig