That said, there's a point at which stupidity stops being mere stupidity and becomes evil: that's when intent--willfulness--is added to the recipe. Amaryllis once again made a totally unilateral decision affecting the entirety of the duchy--and in so doing, flouted the authority of its duke...because the idea behind the decision excited her emotions positively. Aside from the fact that it's effectively rebellion against her duke (this is the second time in the story), it actually--as detailed in the story--exposes the cute little commoner girl daughter she favors to potentially life-threatening circumstances due to Rosemary being a commoner. It's hard to say that Amaryllis did this for anyone's benefit as opposed to having done it for her own gratification--or did she somehow get the idea that she lives the life of a commoner herself, devoid of all the strings attached via nobility to her life's circumstances? The fact that she did these things with a smile on her face/in her heart doesn't change the fact that she's jeopardizing her entire family--and she doesn't care.
Someone did say that the duke Alto is also responsible for this mess, for not having kept a firm hand on her--that's true, and it's also a reflection of today's world. (I'll leave that for the perceptive to work out.) The duke should have appointed some kind of plenipotentiary minister to act in his absence, rather than leave a void for his wife to amble into senselessly and poke around in. Now that Amaryllis has contravened his will twice (and this time in a way that could harm the entire duchy), she should be punished heavily; since they're involved with the throne, however, it'd have to be heavy, unforgiving restrictions--with emphasis on "unforgiving", as it's apparently lenience born of love that got him into this mess in the first place.