The two family members would arrive in Chandigarh via the Wagah-Attari border, the Pakistan High Commission said in a statement.
Sanaullah, who was undergoing imprisonment at Jammu's Kot Bhalwal Jail, was attacked Friday by an Indian prisoner. The Pakistani was flown from Jammu to Chandigarh for treatment.
He was admitted at the Post-Graduate Institute of Medical Education and Research (PGIMER) in Chandigarh.
Till Monday evening, Ranjay continued to be "critically sick" and in "deep coma", a medical bulletin said.
The attack took place a day after Sarabjit Singh, an Indian prisoner in Pakistan, succumbed to grievous injuries following a murderous assault in Lahore's Kot Lakhpat Jail.