Communication between infants and caregivers during feeding opportunities is essential to the progression of infants’ feeding skills. Breastfeeding supports optimal nutritional development and provides an intimate opportunity for mother-infant bonding. However, only a quarter of infants are breastfed in accordance with the American Academy of Pediatrics’ current recommendation. Many factors may influence breastfeeding outcomes, including maternal confidence surrounding breastfeeding. In turn, maternal breastfeeding self-efficacy may be influenced by the infant’s birth order. Birth order may also play a role in parental perception of infant feeding outcomes and sucking/feeding physiology. However, the interrelationships among these factors are relatively unexplored and, thus, remain poorly understood. The goals of this study are to identify the effects of birth order on breastfeeding self-efficacy and parental report of feeding abilities in parallel with sucking/feeding physiological measures in a cohort of full-term infants. Maternal confidence surrounding breastfeeding was measured with the Breastfeeding Self-Efficacy Scale and parental perception of feeding outcomes was measured via the Neonatal Eating Assessment Tool. Sucking physiology was measured with our lab’s custom research pacifier and feeding physiology was measured via the Oral Feeding Skills scale. Results indicate first-time mothers report lower breastfeeding self-efficacy compared to mothers with multiple children. First-time parents also reported more problematic feeding behaviors for their infant. Infants with siblings were more proficient during bottle-feeds. However, no other differences were observed relative to feeding physiology. No differences were evident in suck physiology between the two groups. These findings suggest first-time mothers require more support breastfeeding and bottle-feeding their infants.