The Story of Shelby continues...HELP

You may remember in an earlier post, I rescued an ex breed bitch Newfi. Well our story has moved on a bit and now I need help, Quickly I think!
3 weeks down the line my story is turning scary.
Shelby has progressed to being a somewhat shy, but very patient and attentive dog. She really came out of her shell. Then last week things started to change. She hunts out and destroys clothing belonging to my kids, to the point she will even rifle through my ironing basket to find some! Next she started barking at my nephew, who lives with us- he is 16 and not easily phased, but its a pain every time he walks anywhere in the house. We try to settle her,to no avail. Then tonight she bit at my 5 years old daughter and scared her big time. My OH had made a sandwich for my daughter and Shelby decided to snatch it out of her hand, fingers and allhmy: Im stunned, she seems to have gone from terrified to calm to devil in days.
Im not sure what my next move is, but its got to be at the safety of my kids.

Oh God how scary indeed. A problem with any dog but especially scary coming from a giant!! Well I don't let Ivan have free run of the house at all until the evening when the kids are in bed and even then it is only downstairs. He is just in the kitchen as I am there most of the day anyway and at this stage I can leave the baby gate or the door to the dining room open and he won't leave the kitchen until asked.

Is this a possibility for you? I would not leave her free to get to the clothes or the kids and as far as the snapping at food and the kids I would be thinking behaviourist if it were me especially as she is a rescue. Best of luck I know this is not an easy situation but you can do this you have done really well with her so far xx

All the dogs wander through downstairs, I have a gate blocking the passage to front door and stairs. To partition her off would mean doing so with the other 3, and they behave really well, The 2 pups are now 8 months and wouldnt dream of taking food from you uninvited. Shelby sleeps under my desk at my feet most of the time, clean laundry is in the same room, or should I say ironing mountain.

it may be that she needs some intensive rehab IMO. You need to prevent her doing unacceptable stuff first. She should not be around kids and food, or when exciting play is going on, or even round the children when you are otherwise engaged.
I would treat her as a Project rather than a pet for now. It is very easy to assume a new dog will act the same as the ones you`ve trained and socialised for years, forgetting all the steps in between (this is something I am guilty of, anyway).
Using safety gates or even a kennel and run might be a good idea while you are teaching her how to behave. Then have her out and round the family only when she can be under your supervision, or for a particular purpose (e.g training Down and rewarding when calm.
I know your pups are better behaved - but they have had 8 months more socialisation and don`t have bad associations to counter. It takes a long time (years rather than weeks) to rehabilitate some dogs, and I think she needs to move at a gentler pace.

I agree with this. What I've found with my non-socialised dogs is that they seem to go through a kind of second puppy stage re things they missed out on first time round. The difference is, whereas its quite amusing for a puppy to run off with clothing and everyone expects a pup to bite/nip until they know better, going through this with an adult dog (particularly one the size of a newfie) is a lot more serious. IMO she needs to be treated as you would a puppy doing similar things.

however, given the potential seriousness of the situation, I would definitely think strongly about getting some professional help.

Thanks for the advice. I have shut all the dogs out this morning while we are eating and will continue to do so, until things are much calmer. Will get in touch with a behaviourist today.

Seems like she needs to learn some boundaries - have you thought about using a crate to help with this? Not as punishment, but as a tool to help her.

I think Claire and Daisy started you in the right direction. Now she has settled in, she is following her poorly socialized ways. Have you obedience trained her? It is a good way to start establishing yourself as the leader.

Be careful how you treat the children in front of her. Both her and the kids need the same strict, but loving parent. She needs to see them as other pack members that fall between you and her in rank.

You may not be able to do this on your own. You need at least a good book, perhaps attending a class, and yes, maybe the behaviorist. Starting a young puppy off right is much easier than correcting an older dog with a mature personality.

I am glad you posted that - I was just thinking how much of a puppy Mia seems now, she came to me as a snarling controlling nightmare, but now, nearly a year later she seems such a puppy!

But this does sound scary espech with such a big dog with children around

Why do you have to shut the other dogs out??
One thing I have tried to make sure of when I bring another dog into the house is that the existing dogs life changes as little as possible - if they have earnt their freedoms then they keep them.

I agree with all you have been told here and hope a good behaviourist will help you
In the mean time, a little thing that I had to realise for myself
It is NOT bad for a dog in the short term to have v little freedom and a v structured day
Feed, walk, train, time with children and other dogs is basicaly a training excercise, the rest of the time is chilling in a seperate area
then slowly increase freedoms as the trust builds up

and no eating around the dog until you have trained it not to snatch. Might be an idea to train not to take food or treats from hands at all - just to be safe