What does the Islamic Sharia say regarding the issue of sponsoring an orphaned niece whose father recently passed away, her mother having passed away years ago?

Sponsoring an orphan, which means providing for their expenses and looking after their interests, can be done by anyone, and its reward is great with Allah, as the Prophet, peace and blessings be upon him, said: "I and the sponsor of an orphan will be like this in Paradise," and he gestured with his index and middle fingers. As for حضانة (custody), it is more fitting for embracing the orphan, raising them, and disciplining them, and it is more specific than sponsorship. The ولاية (guardianship) over the minor's wealth, which is overseeing their financial affairs, differs from حضانة and has its own rulings, as does the ولاية for marrying off a daughter after her father's death.