I hate to add an inappropriately serious remark to this discussion, but I remember once reading on a Catholic answer site
an explanation of the Catholic view on this matter. I think the fake sign from Our Lady of Martyrs is heretical, unfortunately.
I suppose that one could tell the child that when he hopefully gets to heaven, he could ask God to see his old pets if he still wished to. There would be no harm in that. For we know that when a person finally sees God, he will not be concerned with seeing old pets or favorite places but rather will be captured in the complete fulfillment of the joy of which old pets and favorite places are but little signs. We adults know that, even if the child does not.
This struck me as kind of awful. It's one thing to say that, gosh, it would be nice if we could see our dogs in heaven, but there's no reason to think that we will; God's will is ineffable, everything we do get is by His grace and it would be impudent to demand more, so we should cherish our dogs while they live, etc, etc.
However, the answer given is that in God's presence we won't get to see the lost dogs, but we just won't care
because just being in God's presence is that great. This is a depiction of being in His presence as an addiction that blots out all of our concern for other beings -- a substitution of divine love for Earthly love and compassion, rather than an addition to it.
I think the Catholics at EWTN need to think this through a bit more. Say something disconsoling, saddening, and disturbing if you must, but don't say something sick
I'm an atheist, myself; I'm not attacking Catholicism generally here. I'm just saying that that particular answer was not at all satisfactory.