The book is called A fall of marigolds and is written by Susan Meissner.
Starting in September 1911, we follow nurse Clara Woods who is working on Ellis Island in New York Harbor. She likes this 'in between place', as she hides from a life she was hoping to have, had a fire not taken her dreams away from her.
Circumstance makes her meet a man fresh off one of the ships, who has lost his newly wedded wife during the passage. Clara identifies with him and possibly takes her nurse duties a step too far...
Scroll forward to September 2011 and meet Taryn Michaels. Taryn is enjoying her life providing a unique fabric finding service as well as selling beautiful fabrics in her shop in Upper West Side, New York.
One day a long-lost photograph appears in a national magazine, and she is brought back to the terrible events of the collapse of the World Trade Towers, the same day her life took some unexpected turns.
It is a lovely story, although I found parts of it a bit too far fetched. Still, it is a throughly enjoyable and from time to time, a very emotional read.