Man's best friend?

Many will say that Dogs are the man's best friend.

I was just lying on my bed and got reminded of my sister's hamster who died previously and how much she loved it and thus cry her heart out when the hamster died.
I guess the best consolation that one can give to somebody who is very attached to an animal is that "don't worry, i am sure ______ is going to heaven and meet you, it is in the hands of God."

But are they like human beings? being able to enter into the spiritual realms of heaven and hell?
Some say that animals have a soul but do not have a spirit.
This means that they are not able to have any feelings but are able to do the daily routines.
Others may argue that animals do have feelings. Evidences of dog's crying and many others do show.
So that means they have a spirit?

I guess we wouldn't really know..but it got me thinking about dogs.
Why are dogs called man's best friend?
what is so special about them as compared to other animals? other pets?
What is so distinct about them that some people choose to have dogs instead of children?
The one reason is, dogs obey instructions and are more obedient as compared to a child.
Obedience is a big quality.
I got reminded that God desires obedience not sacrifice.
Just like any human being desiring for someone that will obey and listen, God desires it too.

If dogs can be man's best friend due to obedience?
Can man be God's best friend because of obedience?

God loves man.