letter received from NVC

My uncle (mother's brother) put the file 10 years ago for immigration for my mother, father, me, my brother and my sister.

We have received letter from NVC under my mother’s name that "The National Visa Center (NVC) received your immigrant visa petition from U.S. Citizenship and Immigration Services. We will work with you to complete your immigrant visa case and schedule your visa interview."

We are going to submit docs but the question came to my mind that my brother and sister are now over 18, sister is married. Will we still all get immigration or only mother and father please advice

Thanks