If you have a brother or sister who is a US Citizen they can file be the petitioner for your green card. This is true even if you share only one parent. The drawback to getting residency through a brother or sister is that it is the slowest way to get a green card. Right now there is a backlog of many years for these cases. You will eventually get your green card but you will be waiting for a very long time.
An experienced Immigration lawyer will likely explore whether there is another, quicker way to get your residency through some other category. Often, a good lawyer will recommend filing multiple applications since there is no limit on the number you can have pending.