A nice read. Title should be "The Detective's Estranged Daughter". Effective use of brief flashbacks the first half of the books, and you know a big reveal is coming at the end so no real surprise.
A few too many coincidences, but otherwise a good story and characters are developed well.
If you like detective books this would be a good beach read this summer; especially as the main story takes place in a snowy February in London.
Lastly, the ending was executed well, and this is the first in a series, but I doubt I will read any; this story is complete. I would read other works by Ms. Thomson.