What is the connection between the novel and JFK?

In Valerie Sayers's novel Who Do You Love, President John F. Kennedy plays an important, yet indirect role within the plot. Set in the 1960s, Who Do You Love follows the Rooney family. A group of Irish Catholic misfits, the Rooneys are going through hard times that include financial difficulties, intellectual differences, and yet another pregnancy.
Not only was John F. Kennedy the sitting president at the time of the novel, but he was also an Irish Catholic—just like the Rooneys. They respect him immeasurably because of his presidency, and they relate to him mostly due to his religion.
In the novel, President Kennedy isn't just busy uniting the nation—after his brutal assassination, the Rooneys (and everyone else in America) are thrown into terrible grief that ultimately unites them together. While finances and other difficulties were ready to break them all apart, it is the tragic death of JFK that allows them to unite in spectacular grief and stay together as a family.