United, The O'Brians, Book Three

Her heart was shattered the day he was taken.
Now a widow, Nan O’Brian’s time for love is a thing of the past. She no longer thinks about herself, but instead, lives for her nephews, doting on them as if they were her own. But surviving is not living, and when an unexpected encounter sparks something she thought long buried, she wonders if a heart can get a second chance.
She was his one and only.
Shamus O’Day spends his time devoted to the memory of his beloved wife. Knowing there will never be another, his existence has become nothing more than a waiting game. But the game changes when he meets Nan, a high spirited, pint-sized woman who sends his world into a tailspin. New beginnings bring new family discoveries and with them, the realization that perhaps life is not finished with him yet.
But with new possibilities comes old trouble.
Now, the unlikely family must unite to protect the one person who brought them together: Darcie has been marked for death in a treacherous game of vengeance. But when the key to her survival lies with a man potentially even more dangerous, the risky solution could bring destruction to them all.