Provided is a composition and method for modulating serotonergic receptor expression, reducing anxiety-like behavior and stress-induced inflammatory response in a pediatric subject, the method including administering to the pediatric subject a nutritional composition including lactoferrin from a non-human source and a prebiotic composition including polydextrose and/or galactooligosaccharides. Further provided is a method for reducing constipation in a pediatric subject by providing a nutritional composition including lactoferrin from a non-human source and a prebiotic composition including polydextrose and/or galactooligosaccharides.提供用於在小兒個體調節血清素能(serotonergic)受體表現、減少類焦慮行為及壓力所誘發發炎反應之方法,該方法包含將營養組成物投與至該小兒個體,該營養組成物包括來自非人來源之乳鐵蛋白及包括聚右旋糖和/或半乳糖寡糖之益生素組成物。進一步提供藉由提供營養組成物以減少小兒個體便秘之方法,該營養組成物包括來自非人來源之乳鐵蛋白及包括聚右旋糖和/或半乳糖寡糖之益生素組成物。