
I agree with that Barbara.
However, sometimes people with a SA dog decide to get another "to keep it company" and then end up with two SA dogs!
It can work.... if the existing dog doesn't suffer from SA and most of all, the second dog trusts and cues from the first.
My rescue girl lived with my sister for some time before she came here permanently. At my sister's she did have SA to quite a degree, pacing a lot and occasional defecation/weeing. Mainly because although there was someone at home most of the time, they weren't directly interacting with her and she was left on her own downstairs.
Within just a few months of coming here her pacing stopped, and she could be left comfortably for up to 4 hrs (wouldn't leave them longer unless unusual circunstances).
Although she doesn't interact a great deal with my other dog, it seems just having him around and tuning into him (he is content and comfortable when left) made a huge difference. I posted above about recording them and I only heard a little bit of clicky-nails pacing from her, then chilled silence. Within a few weeks of her being here I cut her food down to half because she wasn't expending so much energy on pacing and stressing, and was getting a bit porky!