Have you ever noticed how much stress animals can pull out of a situation?
Or, how you can get a person who refuses to exercise with a 10 min walk to keep moving for 40 min when you explain that the dog needs it.
They snuggle and love unconditionally.
That said, I find it an odd thing to watch youth with attachment disorders interacting with animals.
One said, "Oh, you have a cat; I love cats!" as the first words she said when visiting us. Then, she proceeded to chase off the cat and after moving in she'd shove him out of the way on a regular basis and was completely uncaring about the fact that she could hurt him by leaving small elastics everywhere. Interpretation: she wanted us to like her and she saw a cat, so, she figured she should tell us that she liked them. But, really, she didn't attach to anything enough to care about interacting with a cat.
B on the other hand seems to truly have compassion for animals. The only exercise he does is that forced by us by pointing out that the dog needs it. But, he really wants the dog to be happy, so, he does it. The same cat that didn't like the girl who claimed to love him, climbed into B's lap for a snuggle within 2 days of him being here. But, the pets from his previous placement "aren't his" anymore and he "doesn't care about them anymore". So, he attaches in a way while they are present, but, if he walks away he no longer cares. It's harder to interpret. Does he miss them and think that it's better to pretend that he doesn't? Or, does he really not care? His attachment issues are considered to be more serious, but, it's hard to figure out.