Sedra Toldos 120 words; Does Yichus Makes one’s Prayers Better

And Gd responded to Yitchak’s prayers –
Rashi explains, but not to Rivkah’s because his prayers were more powerful since his parents were righteous. [Yevamos 64a]

Why is this so?

It seems to be inherently unfair, their prayers are otherwise equivalent.

Why do we chafe at the thought that children’s spiritual qualities are likely influenced by home and parents when we accept that genetic and philosophical qualities are?

Chazal are conveying a simple message – our spiritual life is not just our own business, it influences the spiritual well-being of our children.

In every field of human endeavour, we recognise the importance of a positive mind. Seeing and feeling spiritual substance in ones family must contribute to those within that sphere. Yitzchak had that advantage.