Infants sleeping with their feet bent all the time may be caused by physiological factors, which is a normal phenomenon and does not require special treatment. But it may also be caused by rickets, trauma and other pathological factors, parents can pay more attention to observe. 1. Physiological factors: the baby’s posture in the womb is the hands and feet curled up, bent, after birth to maintain this position, the baby will feel relatively comfortable. It will disappear naturally when the muscle tone decreases in the later stage. 2. Rickets: Vitamin D deficiency in infants may lead to rickets, which may cause excessive sweating, disturbed sleep, deformed and softened bones and other symptoms. 3. Trauma: If infants have had collisions in daily life, such as impact, parents are advised to take their children to the hospital for a checkup to confirm whether the sleeping feet are always bent due to bone injuries. Infant sleeping feet are always bent may also be caused by other reasons, parents are advised to take their children to the regular hospital for examination and targeted treatment.