This is the thing I was most excited to share, because it was such a strange phenomenon to me, I almost couldn't believe it was happening. I think everyone assumes I have complete control over my stories and characters at all times, but that is not actually the case. Not even close.
I had plans for Legacies. Edward (Colonel Fitzwilliam) and Anne de Bourgh were going to get married and then things were going to happen. I'm not going to say what things, because I'm going to reuse them for Anne, later, albeit not in the manner I expected I was going to, with her as Edward's wife.
No, instead of these two getting together like they were supposed to do, I had Georgiana and Captain Stanton call on Marguerite Durand, the widow of the captain of the Polonais, while they were in Paris. It was meant to be an anecdote, showing how naval captains looked after the wives of their enemy counterparts (war was about as genteel as war could possibly get during this time). Then Marguerite got beautiful, to activate Georgiana's jealousy and insecurity (she and Captain Stanton are pretty much perpetually insecure of each other's love, but rather than make me want to slap them both upside the head, this only makes me love them more as characters; I'm not sure why this is, but it is).
The book came out so long, Marguerite Durand would likely have been cut, had she remained an anecdote. However, at some point during the planning, basically the following occurred, in my head:
Colonel Fitzwilliam: [strides into well-appointed Parisian hotel] Hey, did someone say smokin' hot French widow?
Sophie: Get out of here! What are you doing here?
Col. F.: Isn't it obvious? You wrote a beautiful French widow. Were you just going to leave her here in Paris, all alone?
Sophie: Well, yes. She's an anecdote. She's only meant to characterize Matthew as a naval captain.
Col. F.: You know what would be better than her being an anecdote? Her having a romance with me.
Sophie: You're meant to marry Anne de Bourgh.
Col. F.: Wouldn't be more interesting if I DIDN'T marry Anne de Bourgh? Think of all the potential! Lady Cat will be livid, you'll get to write more grammatically incorrect dialogue, Captain Stanton will be terminally guilty.
Sophie: But I have plans, for you and Anne de Bourgh. And writing Marguerite's dialogue is actually pretty difficult.
Col. F.: You took my arm, at Waterloo. You owe me. Suck it up and write more dialogue. She'll call me mon chéri -- I've always wanted to have a woman call me that, and then make sweet, sweet --
Sophie: Hey, hey, slow down there, soldier. You should be glad you're still alive. I could have killed you off, at Waterloo.
Col. F.: No you couldn't. Readers like me too much. I bet they'd much rather see me marry the beautiful Frenchwoman.
Sophie: I see your point, but if I do this, you're going to have to decide you love her so much that you're willing to live on very little, for the son of an earl.
Col. F.: Yeah, you just keep thinking that, if it makes you feel better. I'm going to make you add another twist, eventually.
Sophie: I won't cave.
Col. F.: Yeah you will. I'm going to twist your arm. You can't twist my arm, because YOU TOOK IT AT WATERLOO. Remember that? Remember how I only have one arm?
Sophie: Okay, okay, I give up!
So the story changed. Fairly substantially, and probably for the better. But it still shocked me a little, that my characters just decided to do what they would do.
This will no more apparent than at the end of Legacies. The whole big Stanton family blow-up was not actually planned. I outline my longer stories before I write them, and all I had in the outline was that Richard Stanton treated Georgiana and Matthew coldly. When I started writing the portion, I decided he should say something insensitive to Georgiana about the baby, which seemed pretty in character for him, and everything else just snowballed from there, starting with Matthew deciding to cut his father's acquaintance. When it all started happening, I just went with it, and I think the resulting bit ended up making Mary's arc, in particular, much stronger. But it wasn't planned.
A bit of the Legacies outline
I'm not sure what to make of all of this. But it has certainly been a lesson, that when I attempt to fully imagine characters, they will do what makes the most sense for them given their situation, and I had better hope that was what I had planned for them, or be prepared to go along for the ride!