"The issue that arises for determination is whether the First Claimant ('the Claimant') is entitled to recover a success fee pursuant to a costs order against the Defendants in respect of work carried by his solicitors for a period after the Claimant's mother was replaced as a litigation friend by the Official Solicitor. ... In my judgment the analysis in Blankley v Central Manchester and Manchester Children's University Hospitals NHS Trust  EWCA Civ 18,  MHLO 7 is clear and it leads to the conclusion that the retainer that was first entered into 2006 has remained effective during the course of the claim unaffected by the substitution of a new litigation friend. Accordingly, the claim for costs in the period after the appointment of the Official Solicitor is not dependent upon the Official Solicitor having entered into a new agreement on 1 April 2013 or indeed founded upon any such agreement. There was already in existence an agreement which was sufficient to ground the liability of the Claimant to pay the success fee under the original CFA for the period after the appointment of the Official Solicitor."