“He would hold my hand, without gloves, when I was feeling really bad,” one of his patients said. He “kept us alive the longest.” Years ago, Michael Kerr penned a letter to his doctor, letting the physician know that he was doing OK, that the HIV medications Dr. Jerry Rabinowitz had nudged him to take were working, and thanking Rabinowitz for helping to save his life. But Kerr never sent the note, embarrassed by the grammatical errors and rambling, run-on sentences. He had forgotten about the letter, lost somewhere in his desk drawer, until Sunday, when he learned that Rabinowitz was one of the 11 people who died in a synagogue in Pittsburgh after a man opened fire during Shabbat services in what is believed to be the deadliest attack on the Jewish community in US history.