Gosh, this is a tough thread. I, too, have always imagined my Sasha running around with his older buddy Trueman up there with Old Claudia the Sheepdog herding the both of them by biting them on their butts. :-) Quigly was like my Sasha. My ex-sweetie calls them "heart dogs," that one dog who has a special place in your heart.
If it helps any, I'll relate a story from far afield. Several of my church members had gone to hear a talk about Christ's second coming. Afterwards, there was time for Q and A, mostly about deep issues. Well, this little girl stood up to ask the speaker, "Will there be animals in heaven?" "No," he replied. Well, the little girl spoke up, and said, "How can that be? Jesus is coming on a white horse." From the mouths of babes, no? And as for that matter, according to the Bible, heaven will not be an endless worship service guided by angels. We are promised perfect bodies (we will not be disembodied spirits), perfect homes, feasts, fellowship, etc. I believe that believers will spend eternity in the company of animals.