Discovery showed that after mind melding to save Michael's life, sarek and Michael were mentally linked to the point they can communicate inspite of being light years away. Michael wasn't initially aware of the link. Given how it was stated more than once that Picard and Sarek retained a part of each other, do you think their minds were linked as well? They might not have been able to telepathically communicate because of Sarek's disease. But if Sarek was in good health, would it have been possible?