When a mother develops rubella postpartum, she should not breastfeed her baby. This is because the rubella virus can be directly transmitted to the baby, affecting the baby's growth and development. Rubella virus is dangerous as it comes from respiratory infectious diseases. The patient is the only source of infection, mainly spreading through droplets, contact transmission, and mother-to-child transmission. Moreover, the incidence of rubella virus infection is very high in children aged five to six months, and the younger the age, the lower the body's resistance and the higher the incidence rate. Therefore, it is best for mothers to temporarily stop breastfeeding during the breastfeeding period.