I have an indoor dog and he's just a small jack russel terrier and sometimes when we take him outside to do his business, my neighbor's big husky sometimes jumps the fence. He starts barking and that makes all the dogs in the neighborhood bark and he just never leaves. Sometimes while everyone is at work/school my pregnant sister in law is the only one that can take our dog out. And she is just terrified of big dogs, we've talked with the neighbors but they still have not done anything. What exactly can I do? Because our neighbors obviously won't do anything.
There are several things that you can do:
Talk to your neighbors. Sometimes they're just unaware of the issue and most responsible pet owners would be happy to work on any issues others are having with their pets. It sounds like you've done this already and your neighbors are apathetic.
File a noise complaint. Use the internet to look up how to file a noise complaint in your area for the excessive barking.
If the dog is getting loose in the neighborhood, you can call animal control - either to report the owners for failure to control/contain their animal, or to have animal control pick up the dog. They can also check that the animal's living conditions are good and proper and no animal abuse is occurring. If the dog is as scary as you describe it, it's very possible he may attack other pets, children, or adults in the area when loose unsupervised. Another option is to pick up the dog yourself and take it to the nearest shelter area (as lost and found). Most of these options create a paper trail on the owners and force them to pay fines to pick up their dog again. In some cases, having to pay fines is enough for bad owners to chose abandonment over fines. If the owners are actually responsible pet owners but too poor to pay the fines, this can create a similar (but sadder) situation.
If the dog is getting loose in your confined yard This is an immediate hazard to you and your pets. If the dog is as aggressive as you described, it is likely a dog fight to the death will ensue in this confined territory space. You must remove your animal immediately when this occurs and put him inside. Call animal control. I would also consider a taller fence, talking to the neighbor about any items against the fence the dog may be using to climb it, and taking pictures and making documentation in case the neighbors decide to sue or countersue if/when a dead pet occurs (having a paperwork trail going from animal control will be extremely helpful in this sort of case).
Be prepared for dog fights Another thing that you can do is to be prepared. The gel form of pepper spray is excellent for breaking up dog fights (spray both dogs or the victim may become the opportunistic aggressor). Know which phone numbers to call, have your phone, or even carry around a dog medic kit. You can watch videos of how to break up a fight and what to do and how to react to misbehaving or overzealous dogs. Merely being mentally prepared can help you keep calmer, which in turn, should help your dog to be calmer and more stable, as anxiety is often a precursor in fights. This doesn't solve your problem, but it can help.
Huskies are said to be quite tolerant of other dogs in general. They are also very energetic being working dogs, and easily escape jumping fences. So, unless you can get a higher fence in place you are always going to risk this dog jumping into your garden.
Perhaps it might help to introduce the dogs under controlled conditions to see if they get on. If they do it might stop the barking if they play with each other.