The Lake House by Kate Morton

In 1933 the youngest child of Eleanor and Anthony Edevane, Theo, disappears.  Since he is only eleven months old at the time, the police are sure they can find him.  But there is not a trace of evidence to what happened to him. 
Seventy years later, Detective Sadie is taking a "holiday" at her grandfather Bertie's home in Cornwall when she stumbles upon the abandoned Edevane estate.  Soon she discovers the mystery surrounding the estate and begins to dig into the past.  Her investigations lead her to an isolated famous mystery author, Alice Edevane, sister to Theo.   With tenacity she pursues all clues and uncovers some unlikely connections. 
This story captivated me.  I found myself making time to read this book outside of my "normal" reading time!  Chapter by chapter, layer by layer, Ms. Morton reveals more about the plot and the characters.  Initially I had a difficult time keeping the characters and the plots straight  as Ms. Morton shifts between different character's point of view and switches between 1933-1940's and 2003.
I liked the neat, happy ending, but some readers may argue that it was too perfect. 
Ms. Morton is a superb writer.

What I did not like: a teen pregnancy, adultery (nothing explicit was written about the affair/no bedroom scenes etc.), that Eleanor claimed she loved two men (her husband and the man with whom she had the affair).
The author does not sugar coat the consequences about having an affair or of  a teen pregnancy.