Problem: In Matthew, the mother of James and John made a request of Jesus. However, Mark states that it was James and John who came to Jesus to make their request.
Solution: It is clear that both the mother and her sons came to Jesus to make the request, since the text declares “the mother … came to Him with her sons” (v. 20). It is possible that the mother spoke first with the two sons closely following to reiterate the request. This is supported by Matthew’s account because when Jesus responds “are you able to drink the cup that I am about to drink?” the Bible says “they said to Him, `we are able’ ” (v.22). So, there is no unsolvable conflict here. The two accounts are harmonious.
“And when he had so said, he shewed unto them his hands and his side. Then were the disciples glad, when they saw the Lord. (John 20:20)”