If you review the instructions to Form I-130, you will find that in-law relationships are not bases for family-based immigration petitions. So, your sister-in-law cannot file a immigration petition on your behalf.
If a US citizen, your sibling can file an immigration petition for you. However, the wait time for sibling petitions is over 12 years (and over 20 years for some countries). Moreover, the intending immigrant cannot adjust status while in the US when the petition is based on a sibling relationship.
Your post lacks the relevant information. You should review your facts and options with an attorney.
Your sister in law should file the USCIS form numbered I-130 (petition for alien relative) along with the I-485 to adjust your current status. (Each of these forms with instructions can be downloaded from the United States Citizenship and Information Service's website.)
There are no in-law relationships that create a direct immigration benefit under US immigration law. However, an in-law can benefit from a petition when a person files for a qualifying relative. For example, Brother A who is a US citizen applies for Sister B. Brother-in-law (spouse of Sister B) can obtain an immigration benefit with his spouse. This is also true for Sister B's children if they are unmarried and under 21. Separately, a person cannot apply to become a lawful permaent resident from within the US from a sibling unless the person maintains his or her status the entire time.