The lose of the primary teeth in the early days can really affect the alignment of the permanent teeth and it can also increase the risk of orthognathic problems in the life ahead so proper care should be taken care of it. Another ECC is not life-threatening if left untreated, and then it may cause bacteria and the children with severe ECC often requires lots of treatments that are costly with hospitalization under the sedation or General anesthesia. But now you don't need to worry...