My understanding is that this book was originally published as part of Little Women, but now it is published as a separate title, which makes sense because I got the impression that this does not take place immediately after the original novel. From what I could tell, it opened six years or so after the start of Little Women, with the four March sisters now grown up.
So, most of the book is about their romantic lives, although it does continue some themes from the original book; for example, Jo's aspirations to become a writer. The writing style is much the same as the first book, although there seemed to be more focus on significant events in the characters' lives; Meg gets married in the second chapter. A lot of the book did make me wonder which of the sisters Laurie would end up with.
The sisters' storylines seem to be a bit more separate from each other now, and many of the chapters will focus on just one of them, before switching to another one of the main plotlines.
For the most part, this is definitely a "feel good" book, but there is also some tragedy too.
If you read Little Women, you'll remember that Beth got ill in that book, and it looked as though she would die. She gets ill again in this book, and she doesn't survive; her death comes in Chapter 17. It still feels a bit surprising that Louisa May Alcott chose to write out one of the four central characters.
I was glad I read this book; it had a good mixture of romance, humour and tragedy, and the ending was pleasingly upbeat.