Finishing someone’s part of the project in secret isn’t kindness. It’s covering for them.

Quietly doing somebody’s share feels generous in the moment, but it hides the problem instead of fixing it. The teacher sees finished work, your partner learns that nothing happens when they do not deliver, and next time the whole thing lands on you again. Real help is visible. Covering is silent, and it repeats.

If someone’s piece is missing, say so to them first and give a deadline you actually mean. If it still does not arrive, tell whoever is grading, plainly and without drama.