Person

Ramkrishna Bajaj

Of the Bajaj family

DNA (Satish John), via Wayback Machine records Ramkrishna Bajaj as the son of Jamnalal Bajaj.

Sources: 1

Parent

Jamnalal Bajaj
- Getting to the very core of the Bajaj family disputednaindia.com
  “This is what happened with the Bajaj family, which owes its origin to Jamnalal Bajaj. Jamnalal had two sons- Ramkrishna and Kamalnayan.”

Children

Source for the figures above

Getting to the very core of the Bajaj family disputednaindia.com
“Jamnalal had two sons- Ramkrishna and Kamalnayan. The latter had two sons, Rahul and Shishir, while the former had three - Shekhar, Madhur and Niraj.”