There are many!
(a) (i) Karna was abandoned by his mother when he was born due to the Social stigma she would have had to bear, had she raised him before marriage!
(ii) Lord Krishna had to be abandoned by his parents for his protection from his uncle Kamsa who was going to kill him the moment he was born.
So both of them were abandoned by their parents when they were born due to the certain acceptable reasons.
(b) (i) Karna had two mothers, namely ‘Kunti’ and ‘Radha’.
(ii) Lord Krishna too had two mothers, namely ‘Devaki’ and ‘Yashoda’.
(c) (i) Despite being a Kshatriya from birth and blood, Karna had to face discrimination on the basis of caste all his Life. He was always called ‘Suta Putra’ because he was brought up in a charioteer’s family.
(ii) Lord Krishna too had to face discrimination all his Life despite being a Prince and Kshatriya. He was always called ‘Gwala’ because he was brought up in Yadava family.
(d) (i) Karna was a great Friend. He knew how to fulfil friendship and what it means to be a real friend. He was a Loyal Friend to Duryodhana all his Life. He even rejected the offer of becoming ‘Chakravarti Samrat’ of Aryavarta for Duryodhana.
(ii) Lord Krishna was a great Friend too. He knew what it means to be a real and genuine Friend. He completely changed the definition of Friendship when he ran towards his best friend ‘Sudhama’ barefoot and without his crown to bring him to his palace.
(e) Even though they are revered as Great personalities, both of them are often criticized for many things despite doing great deeds.
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