Put another way, the very fact of being alive means there is a soul (even in plants and amoebas) and that soul is connected to a realm as real as dimension time yet not at the mercy of temporal shift. The fact that ALL humans will be resurrected --some to life everlasting in God's presence, some not in God's presence-- is an indication that All life will be resurrected and the innocent will remain in God's presence. ALL animals are innocent of spiritual rebellion (because they lack a spirit though they are souls with bodies) thus they are suffering now only because of Adam's fall and the resurrection of Christ has dissolved that curse for them.
Thank you.
While I'm not one to say as others have that I wouldn't want to go to Heaven if my pets don't, I believe God cares for the smallest among us and his care extends beyond life as we know it.
The first and only pet I ever had growing up was a gray tomcat named Smokey. When I was a teenager I was involved in a wreck and spent 30+ days in the hospital. I had to relearn how to walk and was extremely shaky at it when I came home.
Smokey had lived with us for 7 years at the time and knew there were certain parts of the house which were off-limits to him. (He wasn't allowed on the carpeted parts of the house.) My bedroom was down the hall which was an off limit area and was itself off-limits.
The afternoon after I was released from the hospital I was asleep in my room and my Mom came in to check on me. She found Smokey curled up on the bed next to me. When she started to reach for him to pick him up, he hissed and swatted at her which was extremely unusual behaviour for him. She allowed him to stay.
He stayed for exactly 3 days, only leaving my room/bed to eat and to go outside to take care of business. I don't know why he chose 3 days but I can only guess it's because on the third day I had my first follow-up appointment with my Doctor so I was up and out of the house for awhile. He never came back to my room again.
Only Smokey knows why he stayed with me for those 3 days and he took his reasons with him when he died.