u.s. army staff sgt. julian mcdonald of columbus , ohio has adopted a 4-year-old dog named layka who protected him in afghanistan .
despite being injured in 2012 , layka completed the mission with her team and her wounds were treated upon her return to safe territory .
` she was the sole reason why i was living and breathing and able to come home to my son and wife , ' said mcdonald of his four legged partner .