anxeity in Dogs

Question
Hello

i am looking after a friend of my moms parents dog for 3 weeks while they go to Florida.  i am not sure how long they have had the dog for, but i know what it hasn't been for that long.  I don't think the dog is even a year old yet and i think the girl said they got her around 10 months.   any way when they got her the owners before had the dog tied up out side all the time, but now that my mom friend has the dog she is an indoor dog.  my mom's friend told me that she has had a couple accidents in the house. fine no big deal we can help with that.  we got the dog Thursday night and she peed in the house, we think during the night.  that could have been our fault didn't listen for her.  Friday morning we let her out in the morning and while she was out side we looked in the house to make sure she didn't have another accident, and she didn't.  we let her back in the house from outside and she poops in the house.  not in front of us or anything, i walked into the room and smelled it, so we punished her for pooping in the house and cleaned up the mess and she was fine the rest of the day.  Saturday morning we woke up, let her out side and there was nothing, she came back inside and fine the rest of the day until my husband left at 8pm that night.  I was gone from 8am until 8pm and she was outside playing with our dog when i got home.  my husband wasn't even gone for an hour and she pooped in the house.  and it seems that the dog is pooping in the same place all them time.  is this anxiety or just that the dog is not trained to go outside, and if it is anxiety what can i do to stop it.  
thank you

Answer
Rebecca-

It is most likely that she was never housetrained. Dogs are naturally "latrine" animals and will try to use the bathroom in the same area, which is why she is marking the same spot. This is why housetraining works in the first place.

First, please do not punish her for going to the bathroom in the house, unless you CATCH HER doing it. (and then, you just say NO NO NO!! and get her outside to finish) Dogs do not have the ability to connect something they did a few minutes ago to the punishment they are now receiving. And because she was never taught, it's just going to increase anxiety and fear in her because she doesn't realize there is an alternative.

Second, purchase a crate. She needs to be crate trained. Again, dogs are latrine animals, and will not go to the bathroom in their "dens". The crate will be her den. The second her feet hit the floor, she goes outside. She should not be allowed back in until she uses the bathroom and you witness it. You then praise praise praise!!! as she is using the bathroom outside. Even give her a cookie when she is done. When she comes back in the house she should not leave your sight. Watch her ALL THE TIME when she is loose. Take her out every few hours. She should be crated if you are not watching her. Eventually, she will realize the entire house is her den.

You can move her food/water bowls or her toys or bed to the spot where she is going to the bathroom as well, to deter using that spot. Dogs will not mess where they eat.

I hope this helps. Google crate training and positive reinforcement training for more help.