For a Biblical precedent we need only think of Joseph and his coat of many colours, which plays an important role in this week’s reading and shows how sibling rivalry is bound to be the result of parental favouritism and to lead to ramifications that extend over many decades and even generations.
It is indicated by the words the siblings used when they brought or rather sent the blood-stained coat to their father – “We found this; look – is it your son’s coat?” (Gen. 37:32). Not, “our brother’s coat” but “your son’s”. The feelings of brotherhood were gone.
We still hear echoes of this wording these days – “Tell your brother his dinner is ready”… “Is your sister back from school?”. It reverberates amongst adults too – “Do you know what your daughter did today?”
How many times in my own career have I seen families split asunder by favouritism, often over money, and frequently when a parent’s will was biased towards one child as against others.
When a child asks their parent, “Who do you love most in the family?” the answer ought to be, “I have room in my arms for all of you!”
Remember the Akedah – God tells Abraham to bring up the mountain the son he loves, and Abraham – according to the Midrash – replies: “I have two sons, and I love them both” (see Rashi on Gen. 22:2).