Without much ado, I am going to put the inconsistencies in here.
– When Mike’s triplets were first introduced they were said to be all detectives on the force but later on in their own stories people are speculating that since they became Cavanaughs they got promoted to be Cavanaughs
– Until A Cavanaugh Christmas, Andrew, Brian and Mike’s father was a Police Officer. In A Cavanaugh Christmas he was referred to as a detective.
– The American Way: No Ground floor but still mentioned in Cavanaugh’s Bodyguard the first floor of the precinct is called the ground floor
– Andrew Cavanaugh was the patriarch of the family (up till A Cavanaugh Christmas) as his parents were both dead. Now in Cavanaugh’s Bodyguard, Andrew’s father rises from the dead and we find out that he had been living in Miami all the time
– Andrew Cavanaugh’s father’s name was first told to be Seamus Cavanaugh and then it became Shamus Cavanaugh in Cavanaugh on Duty
– Not just that, he has a long lost brother too!
– Then there is Sean Cavanaugh who was dating Sabrina Abilene who becomes Diedre Callaghan in this one. Sabrina was Matt Abilene mother whose name is also changed to Matt Callaghan
– In Cavanaugh Hero we find out that it was Shamus’s father who took the younger kid with him at the time of divorce whereas previoously Shamus’s mother left with his younger brother and there was no divorce there at the time