It is called a Bichon Frise :


What kind of training has this dog received, if any at all?

Can you give us an idea of his kennel situation? When he receives his dinner, is he asked to perform any tasks first?

What kind of exercise does he receive, if any at all?

You know, negligence is a form of abuse and while your in-laws mean well, it sounds like they're indirectly abusing the poor Bichon. All dogs are born with the potential to be well-mannered family dogs, but it is up to the humans to shape them into such canines. If your in-laws can't manage this simple task of training their dog efficiently, report the bite and get the animal control involved. My heart goes out to you AND the bichon because it sounds like neither sides are happy right now, and I would HATE to see the bichon living a life where he is not wanted or loved by all of the family. Bichons are incredibly happy, gregarious dogs who *adore* their family.

Happy, trained dogs do not bite, and it sounds like your in-law's bichon is in desperate need of NILIF, obedience training, and some *positive* attention.

Muzzling him, caging him, and confining him will only make matters worse as he gains not only space aggression, but resource aggression as well.

Lastly, never physically force a dog to move him/herself. This is the best way to get yourself bitten. I know you had no choice, but a dog has two choices: fight or flight. When you take away one option (flight), he will fight. A trapped dog is an agitated dog who's ready and willing to bite. Instead of physical force, let him calm down and entice him out with a yummy treat and lots of praise. If you call him out to punish him, he will not come out again.

Tell your in-laws that these are their two options:
1) Get the dog obedience and NILIF (Nothing In Life Is Free: http://k9deb.com/nilif.htm) trained (offer to help them) OR
2) You report the bite and get the animal control involved and make it clear that you do not want a dog capable of dangerous biting living with your family and young children.