Today on Boston Public Radio: Pulitzer Prize-winning journalist Tracy Kidder and Dr. Jim O’Connell of the Boston Health Care for the Homeless program joined to discuss Kidder’s new book “Rough Sleepers: Dr. Jim O'Connell's Urgent Mission to Bring Healing to Homeless People.” We opened the lines to get listener reactions on the mass shooting at Michigan State University. Juliette Kayyem discusses what we know about the Michigan State University shooting, recent swatting at multiple school districts in Mass, and her latest column in the Atlantic about the unidentified flying objects. Kayyem is former assistant secretary for homeland security under President Barack Obama, and the faculty chair of the homeland-security program at Harvard’s Kennedy School of Government. Jared Bowen discusses the American Heritage Museum’s Hanoi Hilton exhibit, August Wilson’s Seven Guitars by the Actor’s Shakespeare Project, and the Last Dance of Magic Mike. Bowen is GBH's Executive Arts Editor and host of Open Studio. Sy Montgomery discusses new research that finds orca mothers are so drained after raising one male calf that it drastically reduces their chances of having another one. Montgomery is a journalist, naturalist and a BPR contributor. We ended the show by talking to listeners about the toll parenting has.