"Fruit of the Poison Tree", Part 2
aka, "the fifth Burnett episode"
He doesn't even look at Gina in his dream. He never has a single flashback about her, over the course of months, not that we can tell. Ever wonder why?
Sonny is obviously very isolated for the Burnett episodes, including in his own mind. Gina may be even more isolated for this one; even though she's supposedly in contact with OCB, she's still clearly living very much in her own world with her own fake identity, right up until Sonny and Rico arrive just late enough. (Sonny also has to wear a bunch of dark things in this episode because someone has made off with his pure-white shtick.)
"Poison Tree" has an almost-identical opening to "Hostile Takeover" (you can guess which's which):
Gina's dress actually shows up at Celeste's party, on a blonde woman with a face we don't see, before we even and right after we see Celeste:
And now it's time for the person who set this up to pay.
A little hard to know if that's a jacket and t-shirt or dark shirt and tie, at first glance. A little hard to tell which "pretty boy" she's pointing the gun at, for symbolic reasons...
Forgiveness? Maybe. But whether there's one or two or however many Sonnys, you can't see his face.
Celeste is blonde, but there are multiple occasions her hair is made to appear black, either by wearing something over or near it. See the white flowers on the bottle Sonny's drinking out of...? ("Who are you?", indeed...)
So– he never calls Gina "baby", before "Poison Tree"... but he does call Celeste that, a couple of times. With all the references to the arc in the episode, Sonny may not be Burnett anymore, but it probably makes sense that some things from that period are carrying back over. Especially with his chain of calling Gina "Caroline" and calling Celeste "Caitie"... especially if it's heavily implied some part of him was always viewing Celeste as somebody other than that, too.
Why is Gina absent from the Burnett episodes? She's not. She's present on a different level. (Then she gets one of her own.)