The correct order to buy insurance is: first buy urban medical insurance or rural cooperative medical care, which is a national welfare, must buy, and cheap. Then buy accident comprehensive medical care, major illness and old-age insurance (children are education funds).
Now you just need to buy another critical illness insurance, just like your husband. There is also a family of three who each buy an accident comprehensive medical treatment. This premium is relatively low (annual premium 100 or so) and the protection is relatively high.