I'm thrilled that my wife's dog bites her sister
Why would you be happy about such a thing?
It's hilarious to see it. You would not believe me.
It's dangerous and you shouldn't let your dog bite anyone let alone your wife's sister. It's disrespectful to get off all happy because you want to see her get hurt. People will dislike guys like you for showing this kind of attitude.
Why are you being so judgemental. It is just a dog.
You should consider the pain it could cause someone. Most dog's teeth can be quite sharp.