This is from the instructions on I-130
A. If you are a citizen, you may file this form for:
1) Your husband, wife or unmarried child under 21 years old;
2) Your parent if you are at least 21 years old;
3) Your unmarried son or daughter over 21 years old;
4) Your married son or daughter of any age;
5) Your brother or sister if you are at least 21 years old.
B. If you are a lawful permanent resident, you may file this form for:
1) Your husband or wife;
2) Your unmarried child under 21 years of age;
3) Your unmarried son or daughter over 21 years of age.
In your situation, your I-130 would be denied if you apply for parents/siblings before you become a USC.