The Book of Destiny (Kitab-ul-Qadr)
Muslim :: Book 33 : Hadith 6435
'A'isha, the mother of the believers, reported that a child died and I said: There is happiness for this child who is a bird from amongst the birds of Paradise. Thereupon Allah's Messenger (may peace be upon him) said: Don't you know that Allah created the Paradise and He created the Hell and He created the dwellers for this (Paradise) and the denizens for this (Hell)?