What is the ruling on caring for and sponsoring needy and poor elderly people who have no one to support them, by analogy with the Sharia's concern for sponsoring orphans?

Sponsoring the elderly and removing harm from them is a communal obligation (fard kifaya), and it holds great virtue and multiplied reward. It is a relief from distress and an aid to a Muslim brother. Its reward is even greater if it is given to those who are in dire poverty and need, for the most deserving of charity are those who are in the most urgent need, and these are often the poor and the destitute.