food, if ou can get it onto some good puppy food, hills or eukanuber. (sp) both really good foods, there is others as well, dont go for the cheap stuff it ends up costing more because you are feeding more.
when you introduce you new pup to ur older dog do it in a neutral place. that way your older boy wont get upset with a new girl on the block, etc.
any way congrats on the new pup. now all we need is pics