No action for the recovery of real estate sold for the payment of taxes shall lie unless the same is brought within three years from the date when the purchaser became entitled to demand a deed therefor; but if the owner of such real estate was, at the time of such sale, under the age of 19 years or insane, he or she, his or her heirs, or legal representatives shall be allowed one year after such disability is removed to bring an action for the recovery thereof; but this section shall not apply to any action brought by the state, to cases in which the owner of the real estate sold had paid the taxes, for the payment of which such real estate was sold prior to such sale, or to cases in which the real estate sold was not, at the time of the assessment or of the sale, subject to taxation. There shall be no time limit for recovery of real estate by an owner of land who has retained possession. If the owner of land seeking to redeem has retained possession, character of possession need not be actual and peaceful, but may be constructive and scrambling and, where there is no real occupancy of land, constructive possession follows title of the original owner and may only be cut off by adverse possession of the tax purchaser for three years after the purchaser is entitled to possession.