Whenever an order shall have been made for the sale of any such real estate and it shall be made to appear to the court or judge that the interest of the minor or other ward would be promoted by platting such real estate the court or judge may, by order, authorize the guardian either alone or together with the cotenants, if any, or other owners, to make and acknowledge a plat of such real estate in the manner prescribed in ch. 236. A plat made pursuant to such order, certified and acknowledged in manner and form prescribed in ch. 236 and approved by the court or presiding judge, shall be as valid and effectual as if made by the minor when of full age or by the individual adjudicated incompetent before the adjudication. After such plat shall have been duly made and recorded such guardians may make separate sales of any lot or lots, according to such plat, or of such ward’s interest therein in the manner above prescribed.