In plain words
These words of Kṛṣṇa made Arjuna suspicious. When they had come near the inner palace, Kṛṣṇa told Arjuna that Abhimanyu had died. Arjuna grew angry. ‘I entered the war because You were there, because You would protect us. Though You were there, You became the cause of my son's death,’ and in his fury he said, ‘You are the destroyer of our line!’ Kṛṣṇa said nothing, because Arjuna was in grief. ‘Did this war come to kill my son? I do not want a kingdom you cannot enjoy,’ Arjuna lamented. Seizing that moment, Kṛṣṇa stepped in. ‘Arjuna! If the sons of the Kauravas are lost, that does not matter. Is your own son more to you?’ He said. ‘Such selfishness does not become you. In war all are equal,’ and He went on teaching him courage.
The Dharma of the Ātma, abiding as the stream within, is one alone
Aśvatthāmā, at night, while everyone was asleep, cut the throats of the Upapāṇḍavas and killed them. The Pāṇḍavas grieved deeply: how could he have had the heart to kill those infants? Arjuna vowed that he would cut off Aśvatthāmā's head and give Draupadī peace of mind. Then Draupadī came: ‘Your father is the guru of my husbands; you are the guru of my sons. Is it just to kill your disciples' sons?’ she asked.
They did not come in fury; they are not on the battlefield bearing weapons; not the least wrong have they done you; yet, swollen with your might, in the dark, these gentle little children, with no skill in the work of battle, asleep: alas, how could your hands move to kill them!
Because her sons have died, Draupadī has gone mad, it seems:
She is not angry that he seized and killed her sons; this child-killer she tells us to let go, that mad Draupadī! Is this fellow a brāhmaṇa? Why let him go? Kill him here and now! If you will not kill him, with my fist's blow I will split his head open: watch, all of you!