The redness and swelling of the baby’s fingers may be caused by the following reasons: 1. It may be caused by trauma to the hand, which is more common in infants and young children who suddenly and unconsciously touch hard objects around them during their activities, which may cause soft tissue contusions or even fractures inside the hand, and at this time there will be obvious redness and swelling of the fingers. In addition, if the area is pressed by a foreign object or hit by a heavy object, it may also cause a similar injury.2. This condition may be caused by infection in the area, for example, if there is a small puncture injury in the area or a serious systemic infection, it may cause a very obvious infection in the whole finger, followed by redness and swelling, heat and pain in the area.3. This condition is also caused by skin lesions of the finger, for infants and young children, more commonly due to prolonged hand eating, resulting in eczema and other skin diseases. In addition, if the area is exposed to irritating chemicals, or by mosquitoes and insects bites, may also produce similar skin irritation, resulting in redness and swelling.