This paper explores the potential of combining different isotope systems from different tissues to improve resolution when reconstructing breastfeeding and weaning practices (BWP) in archaeology. Additionally, we tested whether changes in diet can be detected in deciduous teeth. Rib collagen samples from 22 infants/children from the archaeological site of Bacuranao I (Mayabeque, Cuba) were processed for nitrogen (δ¹⁵N) and carbon (δ¹³C_co) stable isotopes and assessed using a Bayesian model (WARN). In addition, enamel of 48 teeth from 30 infants/children were analyzed for oxygen (δ¹⁸O_en) and carbon (δ¹³C_en) stable isotopes. Data revealed that the timing of weaning cannot be characterized precisely by analyzing either δ¹⁸O or δ¹⁵N. While a depletion in both δ¹⁵N and δ¹³C_co is only evident after one year, the WARN model suggested that the weaning process started at around 3 months and ended around 1.7 years. Most teeth were enriched in δ¹⁸O_en compared to deciduous incisors, suggesting a breastfeeding signal. However, a high variability in δ¹⁸O was found between similar teeth from the same individuals. Higher enrichment in δ¹⁸O_en, and variability, was observed in tissues formed during the first six months of life. A δ¹³C enrichment of 1.0‰ was observed among deciduous teeth and ribs. While most individuals enriched in δ¹⁵N showed enrichment in δ¹³C, the δ¹⁸O values were more variable. Our data suggests that stable isotopes of deciduous teeth, especially δ¹³C_en, can be used to detect changes in diet during the weaning process. It is also possible that the δ¹⁸O enrichment observed in M1 is influenced by the effects of cooking techniques on weaning foods. The combination of multiple isotope systems and tissues overcome some of the limitations posed by single tissue approaches.