I want to understand the full implication of sponsoring a relative for green card.
The person is 65 years old, and has never worked in the US. If I sponsor them, in what ways would I be liable for their medical and other bills once they get the permanent residency?

Would they qualify for medicare and medicaid based on their age and permanent residency status, and no/low income group? To what extent would they be covered, and would I be liable in any case?
State: California