Which grandson of the Prophet (PBUH), son of Imam Hussain (RA), survived the Battle of Karbala due to illness and continued the family lineage?

Explanation

– Ali Zain-ul-Abideen, the son of Imam Hussain (RA), survived the Battle of Karbala due to illness that prevented him from participating in the fighting, subsequently continuing the family’s lineage.
– He later became recognized as a significant religious figure in his own right, known for his piety and a well-known collection of supplications attributed to him.
– For exams, note that his survival ensured the continuation of this particular branch of the Prophet’s descendants through subsequent generations.