Khadr was compensated by the Government of Canada for its own failings (under Liberal and Conservative governments) toward him - a Canadian citizen - facing ongoing torture.  

The issue of whether Khadr did in fact kill a US serviceman - a conclusion reached in what was almost certainly a biased hearing kept away from formal US justice followed by the threat of indefinite jail time (and likely more torture) unless Khadr signed a confession to enable belated extradition to Canada -  is a whole other matter.  He is not being rewarded for that.

Yes it's tragic that Ms. Speer lost her husband in battle (whether of not he was killed by Khadr), but that is a separate issue and I don't see how Canada should be liable for it.  Wars have always left behind grieving widows and children - sadly, it comes with the turf and the Speers must surely have known that.  I hope the United States is providing Sgt. Speer's family adequate support, but it is not our role to do so.