Yudhishthira’s answer, in the Mahabharata, is that a mother is heavier than the earth and a father is higher than the sky.
Four brothers lie dead beside a lake. They drank from it without answering the questions of the spirit who guards it. The fifth brother agrees to answer, and one of the questions is this: what is heavier than the earth?
Give me a hintThe hint
Not a thing but a person. It’s about worth, not weight.