What worked for Caney (with a lot of consistency) was to turn our backs whenever she jumped, and not turn around to greet her until she was calm. Every time she would jump we turned right back around. We have guests over frequently and some of them did not cooperate in helping us train her, but most of them did and that really helped. When Caney was about a year old she stopped jumping up. It was almost as if she turned one and just calmed down.
In your situation I would be firm with your guests who come over about not letting Roxy jump on them. Tell them that you're trying to mold a well-behaved dog and that the training process will be much quicker and easier if they cooperate. It will also be less confusing for Roxy if all humans have the same "rules" with her. Explain that her habit of jumping makes it very difficult to socialize her with children, which she would very much benefit from.
If your guests will do this then you won't need to leash Roxy in the house with them. I would however leash her when she's going to be around young children, since she could easily knock over a child. You don't want them to be afraid of her, and you don't want her to learn that knocking them over makes them an easy target for kisses
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Zoë
Creek - Fawn Female, born 03/27/2001
Caney - White Female, born 03/26/2007
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