Well my dog died of parvo.?

well i took my 3 month pit bull to the vet yesterday 10-12-09. he was diagnose with parvo. he got sick since Saturday :( :( :(. he died today between 4 n 6 o clock... but now my question is how can i disinfect my back yard with out harming the gr, so his brother wont get infected. i was reading i could use bleach that would kill the gr but my dad would kill me and the dog... how can i find out if my other dog got infected he wont eat or drink.. i had to feed him with a spoon today he ate some n drank a lil bit of water.... so i just went and gave him pedilyte just in case he might have parvo so he wont dehydrate. but at the same time im not so sure if it can be depression they been together for 3 whole months from morning till night, since he saw his brother die and no they were not together ever since Sunday night... i know there could be a possibility that he could be infected is there something i could do or just take him to the vet to be more accurate...what can i do to prevent my puppy from getting parvo... he already had his 1st booster set and is going again this week end for the 2nd set either email me for more istant chuki3_56@yahoo.com