D.C. Code § 21-148

When a guardian or, in case of his refusal to act, a next friend, deems that the interests of the ward will be promoted by a sale of his freehold or leasehold estate in lands, for the purpose of reinvesting the proceeds in other property or securities, or by an exchange of the property for other property, he may file a verified petition in the court, setting forth all the estate of the ward, real and personal, and all the facts which, in his opinion, tend to show whether the ward’s interest will be promoted by the sale or exchange.