https://variety.com/2021/tv/news/max-rosenthal-dead-95-everybody-loves-raymond-phil-1235006177

The elder Rosenthal appeared on his son Phil's shows, recurring on Everybody Loves Raymond and making cameos on Somebody Feed Phil and its PBS predecessor I’ll Have What Phil’s Having (https://www.youtube.com/watch?v=ZLh_OV44CXk). “As heartbroken as we are, we are so grateful that he was our dad, our grandpa, our friend, our favorite and funniest TV star and the role model for how to live 95 years while being the sweet, gentle, kind, compassionate and really, really funny,” Phil Rosenthal wrote on Instagram, calling his dad “the biggest influence in my life.”

RIP. I didn't know Phil Rosenthal's mother had passed away too. His parents both would appear on video calls in the episodes of Phil's culinary travel shows.

My favorite Max episode is definitely "Who Am I?" In the first steam room scene, the guys at the lodge accept Ray as one of their own, but in the tag scene, one of them (Albert, played by Ray Romano's real-life father) takes exception when Robert makes an innocuous joke. As Frank leads Robert out of the room, Max tells him to "bring back the funny one" while restraining Albert. :)