The I-130 petition is used to establish the claimed family relationship, nothing more.
At a later date, the I-130 petitioner will also need to file an I-864, Affidavit of Support, even with zero income and assets (unless deceased). Additional folks can join as co-sponsors and/or joint-sponsors (or a "substitute sponsor" if and when the I-130 petitioner dies before the Immigrant Visa is issued). This is a separate issue that will come into play around a decade after filing the I-130 for a sibling (or up to 30 years later for some countries).