I think the phenomenon described below is related to a hypomanic quality in Moon in Sagittarius (a mid-1970s study showed Sag Moons tended to score high on MMPI Scale 9).
(Some notes/observations from another thread, for consideration later...)
"...{some of} the most optimistic Sagittarians I know (with moments of bubbly) are double Sagittarians (one guy, one gal)... I find a number of Sagittarian Moons (not Suns) that have stretches of this bubbly quality and - here's the interesting thing - the deeper they are in real, diagnosed mental illness, the more likely they are to have high-energy, defiant, and (yes) bubbly expressions. Over-compensation? Maybe. But, more generally, I think, it being a Moon sign, that I'd call it adaptation through positivism (not exactly the same thing as over-compensation since, say, an Aquarius Moon in the same place would be "adaptation through forcing oneself further outside the mold," or some such thing). But I do have quite a few Sag Moon females (I can't find a any men in my personal collection) that are cyclothymic... Most of the Sag Moons, though - the healthy and less healthy ones - are devoted to ideals and values. I'm talkin' from George Washington to Adolf Hitler in the public sector, several personal examples that are culture and family supportive, etc. (This resembles Moon-Jupiter effects in mundane astrology.)"