The goal of this clinical trial is to learn the effect of vitamin D as an adjunctive therapy for preterm neonates with sepsis measured by the outcomes, which are sepsis score and C-reactive protein after 7 days. The main questions it aims to answer are: Is there a difference in the results of the sepsis score (Modified Tollner Score and Sepsis Prediction Score) between groups of preterm neonates with sepsis who were given vitamin D as adjuvant therapy at doses of 400 IU/day, 800 IU/day, and those who were only given antibiotics? Is there a difference in CRP levels between groups of preterm neonates with sepsis who were given vitamin D as adjuvant therapy at doses of 400 IU/day, 800 IU/day, and those who were only given antibiotics? Participants will be divided into 3 groups: Group 1 consisted of subjects who were given only antibiotics due to medical conditions requiring fasting. Group 2 consisted of subjects who were able to receive enteral nutrition, were given antibiotics, and were supplemented with vitamin D3 at a dose of 400 IU once daily for 7 days. Group 3 consisted of subjects who were able to receive enteral nutrition, were given antibiotics, and were supplemented with vitamin D3 at a dose of 800 IU once daily for 7 days.