I feel sure that if Julia has studied up on vampires, she also has a pretty good idea of how their servants behave. She probably had some contingency plans for dealing with Willie, too.
At this point, I think Julia is more interested in Barnabas as a patient than as a person and probably attributes his actions with Maggie to his disorder. And yes, I do think she needs him to be up and around, the better to study the effects of her treatment. We don't know yet whether she's planning some sort of medicinal brew or injections. I imagine it wouldn't be too easy to give someone, say, a hypo while they're in a coffin. And it's hard to swallow liquids while you're lying down.
It's nice to see Maggie back in her own room, surrounded by all her own things and with her pop and her beloved Joe.
Dr. Franz Mesmer first started hypnotizing people at parties in the 18th century, so Barnabas might have heard of it before he was confined to the coffin. Mesmer didn't use hypnotism for medical purposes and was considered a charlatan, which might explain Barnabas's skepticism about the process. (Mesmer was a friend--and mesmerizer--of Mozart, who used mesmerism as a plot element in one of his comic operas.)
Barnabas and Julia have an interesting conversation on the subject. Julia is going to make house calls (!) to continue treating Maggie. She tells Barnabas, I plan to visit Maggie regularly as her doctor to make sure she continues to forget--as long as you continue to cooperate. And if I don’t? he asks. Your safety depends on me, she reminds him. You’re going to great lengths to continue, he comments. I’ll do whatever it takes, she answers. That seems to be anything, Barnabas observes, not without some wonder at her medical dedication. Anything to save a human life, Julia says firmly [spoiler](words that she will remember, alas!).[/spoiler]
While they're talking, Julia calmly inserts a cigarette into a holder and lights it at one of the candles. I wonder why Barnabas lets her, but then some of the strangest twentieth-century customs (or clothes) don't seem to faze him at all. Possibly her smoking is less of a surprise to him now that he knows that twentieth-century women can be doctors. After a final warning to Barnabas that if something happens to Maggie she will expose him, she sails out the door.
Meanwhile, we see that Sarah is also looking out for her friend Maggie….