I’m not sure which “Sudarshana Kumari” you mean. In Jain kathā-literature the name Sudarshanā/Sudarshana occurs for different women in different texts and traditions, so the identity of her brother changes by context (text, lineage, and era). Please share the specific Jain text (e.g., Kalpasūtra commentary, Ācārya’s kathā-granth, or a well-known Jain story collection) or any related names (parents, husband, city), and I will give the precise brother’s name with the correct tradition-specific details.