I'm so sorry to hear about your friend's departure.
I heard a story once, that said that when we die and that we arrive at the Big Pearly Gates of Paradise, all the animals we've known and cared for will be there waiting for us... they're the one who will decide if we go in or not.
Looking at Panther... I can see so much love in his eyes that I have no doubt you will be well escorted through the Gates.
Beautiful portrait of your little friend.