My wife and I dont have children and dont PLAN to (if you read about my surgery last week you know the story), but out cats are like our children. We lost one a few years back and at times I still miss her.
I think we could all learn a lot about unconditional love from our pets. Think about it, if you come home and are having a bad day, they don't care, they just want your love, and want to give you love in return. If we were more like our pets, the world would be a MUCH better place. they dont hold grudges, dont get mad at you (at least not for long), want to be by your side, etc. I'm blessed to have the animals we have, and I'll care for them as well as i can for as long as God allows them to be with me.