The relationship between the sisters was so well written. They bicker but it’s obviously they love each other. When they both now the other is hiding something but neither of them fesses up. That is timeless. 
And the mom was fantastic. I love that when Elinor asks her mom to confront Maryanne about whether she’s engaged or not the mother responds that if Maryanne wanted her to know she would’ve told her already. I also liked when Sir John is telling the mom that Elinor and Maryanne would be trying to “catch” Willoughby because he is such an eligible bachelor she responds with, “Mr. Willoughby will be incommoded by the attempts of either of my daughters towards what you call catching him. It is not an employment to which they have been brought up. Men are very safe with us, let them be ever so rich.”
What a boss way to say, “don’t call my daughter gold diggers.” 
And what a f*** boi that Willoughby was. I am glad that in the end Maryanne realized what a waste he was. 
Lastly, I am convinced that Margaret existed only to remind readers that the youngest children are almost always forgotten and basically raise themselves. (I am the third child.)