Strange behaviors.

Well... there're 2 strange behaviors for my 8 yr old boxer:
Let me put you some background... I'm a student coming to the US, I was hosted by a family and they have a boxer named Shadow. So I am kinda new to her. But she's friendly and she really appreciates me since I walk her, play with her alot...
THe 1st behaviors is: Whenever the family members got into arguements or laugh or have a visitor, she'll bark really loudly. And noticably, when I talk to mom -- she may be a pack leader in shadow's head, she will also bark.
The 2nd behavior is: She defecated inside the home. You may guess that it could be in my room. Well, partially right, she also did that in Danielle's -- a family member-- 's room.
So.. can anyone tell me what make Shadow do such thing? And about the method to get rid of such annoying behaviours?
Thanks.

Just a guess but she is probably barking because of the raised tones of voices (excitement). If she is 8 yrs old, that is pretty old for a Boxer and the pooping on the floor could be a result of that. When some dogs get older, they can lose control of their bowels...OR, she could be in the early stages of dementia and just "forgot" where to go. I don't know that much about Boxers but I don't think they tend to live past 10 yrs. Someone correct me if I'm wrong, please.

Jessie

It could also be a "claiming" behaviour, particularly if she's pretty close to the two of you.

Well yeah.... I'm new to her. Only like 1.5 months since we knew. The other one is kinda cranky.
She's better now.
Thanks for your ideas.