Yes. Even if you're not directly providing physical care to someone with a life-threatening illness (e.g. cancer), you're probably supporting them emotionally. As this can impact your own wellbeing and potentially your studies, it's a good idea to let your university or college know, and to ensure support is available if you need it, should your circumstances change.
For more support, Hope Support Services helps young people aged 25 and under when a close family member is diagnosed with a life-threatening illness.