Go to the Bible for your answer......as with humans....the dead sleep until the last day .....then Christ returns for the dead ....animals sleep maybe should pray that your beloved pet will be raised  that day also but it is up to God...the devil would like us to believe that we fly around as spirits or reincarnate but that is not Biblical...

Thessalonians 1  Chapter 4     15 For this we say to you by the word of the Lord, that we who are alive and remain until the coming of the Lord will by no means precede those who are asleep. 16 For the Lord Himself will descend from heaven with a shout, with the voice of an archangel, and with the trumpet of God. And the dead in Christ will rise first. 17 Then we who are alive and remain shall be caught up together with them in the clouds to meet the Lord in the air. And thus we shall always be with the Lord. 18 Therefore comfort one another with these words.