Mental health issues are widespread and significant among individuals with serious illness. Among patients receiving palliative care (PC), psychiatric comorbidities are common and impact patient quality of life. Despite their prevalence, PC clinicians face challenges in effectively addressing the intricate relationship between medical and psychiatric disorders due to their complex, intertwined and bidirectionally influential nature. This article, created collaboratively with a team of psychiatric-palliative care experts, is the second in a two-part series examining the bidirectional relationship between medical and psychiatric illness in PC. This article explores 10 prevalent psychiatric manifestations associated with severe illness and its treatment. Building upon the first article, which focused on 10 common physical manifestations of psychiatric illness among patients receiving PC, these two articles advocate for an integrated approach to PC that prioritizes mental and emotional wellbeing across the continuum of serious illness.