The Cabinet of Curiosities by Douglas Preston and Lincoln Child

Just got into the Pendergast series and love it! I read 'Relic' and skipped the second book ( im borrowing them from a friend and she told me its not a necessity to read the second one so i skipped to the third)
Dewey's Nine Lives by Vicki Myron
the second book in the Dewey books
and
Its very emotional and heartbreaking, its one that at times i want to put down,but want to continue reading at the same time.