###Human: What causes lump below the jaw with pain while swallowing in a child? ###Assistant: Hello. The mass or lump that is being felt may be inflammation of local gland due to infection or lymph node enlargement. Both of these will respond to the antibiotics given. In case that it does not resolve, then a further workup is recommended which include radiological, pathological as well as blood investigation. Followup clinical examination is necessary to delineate any kind of pathological condition. So followup visit to a pediatrician for clinical evaluation is necessary.