Salear most of what you wrote is incorrect.  The father was killed, in Pakistan,  some 2 months after this incident.  Khadr was wounded from the bombardment.  Remember he also lost and eye.  When the trooper entered the building he shot one occupant in the head and then seeing Khadr leaning against some brush so he shot him twice in the back.  There is even speculation now that Speer may have been killed by a grenade thrown by the American troops.  Different grenades and the shards in Speer were from an American  grenade.
This is all of that has been in the news,  you really should read more.  Th CBC has a interesting you tube 5 part documentary on the Khadr situation