In all cases where a deed or deeds of mortgages or other conveyances of land dated prior to the first day of January, 1926, purporting to convey lands have been registered in the office of the register of deeds of the county where the lands conveyed in said deeds are located prior to said first day of January, 1926, and the acknowledgments or proof of execution of such deed or deeds and the private examination of any married woman who is a grantor in such deed or deeds have been taken as to some of the grantors, and the private examination of any married woman grantor in such deed has been taken by an officer who was himself one of the grantors named in such deed or deeds, such defective execution, acknowledgment, proof of execution and the private examination of such married woman, evidenced by the certificate thereof on such deed and the registration thereof as above described and set forth, shall be and the same are hereby declared to be in all respects valid, and such deed or deeds or other conveyances of land are declared to be in all respects duly executed, probated and recorded to the same effect as if such officer taking such proof or acknowledgment of execution or taking the private examination of such married woman and certifying thereto upon such deed or deeds had not been named as grantor therein and had not been interested therein in any way whatsoever. (1937, c. 91.)