Take your dog for a walk or play with it regularly to reduce its anxiety and praise good behaviour. Hopefully they will then settle. Some rescue dogs retain anxiety forever and although they settle and are happy in their new surroundings and with their family, they are forever fearful and may need a supplement to help calm them. A natural supplement is always best in my view together with lots of love and exercise. Separation is always tricky for such dogs but if they are tired and it’s part of a routine they may get used to it in time. Others will need a supplement to help.