Posted:
Great explanation Vibhishna!👏
I'd also like to add that Yudhistir was known as Dharmaraja (not only because he always followed Dharma, but because he was the son of Yama Dharmaraja) and Bhima was also known as Pavan Putra. They were referred to as the Pandavas, because it was easier than referring to each of them by their different fathers' names, and also because like Vibhishna said, Pandu thought of them as his own sons and not any differently.
Also, I think Hanuman is referred more as Vayu Putra because Vayu Deva played a greater role in his life than Kesari, but he is also referred to as Kesari Nandan from time to time.
Anupamaa
