I always thought that Archana, Purvi are the two most consistently golden hearted people in PR. Even Arjun, Sulochana Ji (most often, especially in Arjun-Purvi's case). The only thing which Archana needs to do now is to bless arjun and purvi, because she has it in her to do it. Arjun has passed his test with flying colors.
He finds out that it is only because Purvi, his wife's adopted child has created a space for herself in Arjun's heart. He accuses Arjun but never raises his voice at the adopted child, takes his anger out on his wife, which none of us liked, and think is wrong, but never accuses the orphaned child, sweet Purvi, once adopted by his wife.
He feels anger for a long time, but when he realizes that Purvi has been kidnapped and sees tears in Archana's eyes, he takes it upon himself to save Purvi and shell out as much money as is required. His favorite daughter decides to emotionally blackmail him to not help Purvi, but he still does. He does not listen to her. His actions speak louder than words. He along with brave Arjun, have saved Purvi from the kidnappers.
I know Manav has made many mistakes in his life, but this act of complete kindness and compassion for sweet Purvi shows what a golden heart he has. He seems to have forgiven Arjun too now.