Mathai’s only son Dileep was born on the 29th December 1948. Being a B.Sc. graduate, Dileep holds a Diploma in Advertising. Now he is running his own advertising company in Mumbai. Anina, the daughter of Varkey Koshi of Chengannur Vaidyanveettil is his wife. Anina obtained a B.Sc. degree and a Diploma in Montessori Teachers Training. They have a daughter named Reshma. Graduated with a B.Sc. & M.B.A. degrees, Reshma is an employee in Tata Consultancy Services. Her husband is Robin, son of Mavelikkara Puthenpurackal Cherian. Robin holds B.E. & M.B.A. degrees and is a Manager at Reliance Industries, Mumbai. Dileep resides in Mumbai with his mother.