Separation anxiety

I was just wondering, with regards to separation anxiety (which I am so lucky not to have with Nifty)
Would “getting a canine friend” help with an anxious dog or would it only make matters worse ? (Jealousy, rivalry, winding each other up, “contageous bad influence” ?)

Provided the other is a calm dog, I think it helps. Millie's not brilliant on her own but is fine if left with one of the others. Her mum, Roxy, was horrendous for SA in kennels, she would howl and chew, but was absolutely fine when rehomed to live with another more confident dog.

I don't think something like this is learned from others unless the dog isn't 100% anyway. Clearly if you had two nervous or worried dogs, they could make each other worse.