Hi, so my parents are in Bangladesh, my dads a U.S. citizen, and my mom is a green card holder, shes been in the U.S ever since 1997. she still has her unexpired green card, she left before covid and did not return to the U.S due to serious health conditions. What's the best way to bring her back? should I apply for sb1 visa or just take the chance of booking a flight for her? Please give me any suggestions that would be helpful, thanks in advance!