You, being a U.S. citizen or a U.S. lawful permanent resident or a non-citizen U.S. national, must file a separate Form I-130, Petition for Alien Relative, for each eligible relative. You may file as many I-130 petitions as you want, as long as you meet the I-864, Affidavit of Support, financial requirements for being a sponsor.
Please do not forget to prove that there is a family relationship between you and the beneficiary and to include the corresponding evidence to the I-130 petition. Additionally, if you are filing for your spouse, he/she must complete and sign Form I-130A, Supplemental Information for Spouse Beneficiary.