Here again, I have, in an earlier post, given a relevant quote which proves beyond doubt that Dury and Karna were friends from their boyhood days. Re-posting once again
From the Santi Parva, Narada's conversation with Yudi about Karna
[QOUTE]
In early age he made friends with king Duryodhana, led by an accident and his own nature and the hate he bore towards you all.
From the CE / (Shanti Parva, Adhaya 1 Verse 8)
Sa Sakhyamagmad Baalye Raja Duryodhanay vai
...
Baalaye is the word used here. Meaning : 'From his boyhood.'
And there is no ambiguity here. 'Karna' refers to Radheya Karna, not anyone else.
firslty what boyhood means in dwapar yug isn't clear
abhimnayu was around 30 years when he died was still considered a minor so boyhood here could very well mean after rangbhoomi as well
same goes for early age
in any case what i am saying is from the time karan left for parashuram till rangbhoomi there was no association between the two which will explain why in rangbhoomi no one recognizes him
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