The Best of Intentions — Susan Anne Mason

In the aftermath of WWI, Grace Abernathy is determined to reunite with her family, crossing an ocean to convince her widowed sister to return home to England. Yet Toronto holds more tragedy and her nephew Christian is now in the custody of his paternal relatives, the formidable Easton family, who rejected Grace's sister because of her low social status.

Unconvinced the Eastons can be fitting caretakers, Grace jumps at the chance to be Christian's nanny and observe the family up close under an assumed name. In the course of her new position, she is shocked to discover herself falling for Andrew Easton, the boy's guardian. Unfortunately, Andrew is promised to a spoiled socialite who will make a terrible stepmother for Christian. Will Grace be able to protect her nephew ... and her heart?