FIRST GHANA BUILDING SOCIETY v. ADDY Practice and procedure—Action—Person under disability, by—Need to sue by his next friend acting by a lawyer—Defendant not entitled to plead that plaintiff in fact not suffering from mental disorder—Defendant entitled to challenge capacity of next friend to sue—Mode of challenge—High Court (Civil Procedure) (Amendment) (No. 2) Rules, 1977 (LI 1129), Order 15, r. 12 (1) and (4).