No person shall be liable under any provision of the general statutes for the support of a parent who wilfully deserted such person continuously during the ten-year period prior to such person reaching his majority. For the purposes of this section, wilful desertion means total neglect of parental responsibility in failing to provide reasonable support and care within the financial capability of the parent. Any person claiming the provisions of this section as a defense shall have the burden of proof of such wilful desertion.