Anna Miller, a 70-year-old resident of Adelaide, Australia, has led a fulfilling life and has accumulated significant wealth through her successful career as a philanthropist. She never married and has no immediate family or close relatives. Anna believes in making a positive impact on society and wishes to leave her entire estate for a worthy cause that aligns with her values.As Anna approaches the later stages of her life, she is focused on establishing a meaningful legacy that reflects her philanthropic spirit. She wants her wealth to support a charitable cause that she deeply cares about.Anna has chosen to leave her inheritance to "Hope Foundation," a non-profit organization dedicated to providing education and healthcare to underprivileged children in developing countries. She believes that her wealth can make a significant difference in improving the lives of these children and helping them realize their potential.

Question:

Discuss the legal considerations and challenges that might arise when ensuring that Anna's wishes to leave her inheritance to Hope Foundation are honoured after her passing.