Dear Anita – Thanks so much for your reply. One of my friend asked the Prof for this sudden change and was told that we should stay in touch with students from our age group as the Profs’ life stage is different. Why it’s a little surprising is that the Prof never said anything all these years when we wished them on b-day, festivals etc. May be the Prof wants seclusion and keep a low social circle, only with same-age people/relatives and not with students. Unsure why he said that Profs are just guiding lights and not someone whom one should remain in touch forever. Some of us feel it could be a personal setback, which has brought about this sudden change. We just hope and pray, things work fine for him very soon. Thanks again.