I always liked Jack Boyle, The actor who portrays him, Peter Hermann, cracks me up everytime I see him. He so perfectly portrays the "stuck on himself pretty boy" grating upon everybody's nerves who has to deal with him, that I've become a fan.

Now, with his full time gig "Younger" coming to a close, perhaps he's got more time available to grow the Jack Boyle character on Blue Bloods?

Rumor has it he's gonna show up in the season 13 premier and offer to finance Erin's campaign for DA.

https://outsider.com/american-entertainment/tv-2/blue-bloods/blue-bloods-is-jack-boyle-actor-peter-hermann-returning-in-season-13/

Hope this ends up being true. Jack Boyle, along with Geoff Pierson's "Jimmy" (Grace under Fire) and "Jack Malloy" (Unhappily Ever After) were among my favorite scoundrels...all time