Penn leaned forward. ‘A female black eagle lays two eggs. The first hatched chick pecks the younger one to death within the first few days.’
Alison nodded. ‘Among spotted hyenas, sibling competition begins as soon as the second pup is born.’
‘And if we were filming an episode ofSpringwatchthis would be riveting, but…’
‘How about Cain and Abel, Esau and Jacob, Leah and Rachel.’
Kim frowned. ‘Stace, I’m not sure the Bible is—’
‘It’s not just the Bible,’ Alison added. ‘Sisters and actresses Olivia de Havilland and Joan Fontaine were rumoured to hate each other.’
‘The Gallagher brothers,’ Penn added.
‘Rudolf and Adolf,’ Alison said.
‘Who?’ Bryant asked.
‘Dassler. German brothers. Couldn’t get along; one established Puma and one established Adidas.’
‘Same businesses?’ Kim asked.
Alison nodded. ‘Competitive siblings will often follow each other into similar careers. Siblings tend to fight because one has displaced the other. In many Asian countries the roles are determined by cultural norms. The eldest son is expected to assume greater responsibility for the family’s welfare and receives a greater share of the inheritance.
‘Younger children are expected to show respect and obedience to elder brothers and sisters, and in return they expect care and guidance. In other cultures, parents include the older child in caring for the new child. Sibling rivalry is considered the most common form of bullying.’
‘How does it all begin, though?’ Bryant asked. ‘I have siblings but we’re not competitive.’
‘Obviously, it starts with the parents. If there’s a lack of structure, tension from above, no family hierarchy, negative attention or no attention and lack of problem-solving solutions, childhood becomes an adventure sport.’
Alison turned to Bryant. ‘If one of you had a toy and the other wanted it, what was your parents’ response?’
‘My mum would ask us who had it first.’
‘Exactly. A simple statement with guidance. The first child who had the toy gets to keep it. What if your mum had said to sort it out yourselves?’
Bryant considered. ‘We’d probably have fought.’
‘Exactly, rivalry has to be kept within healthy and constructive bounds. There are guidelines like ignoring tattling, don’t compare, allow expression of feelings without blame, encourage sharing but don’t force it, individually value and spend time with each child, decrease—’
‘Enough,’ Kim said, holding up her hands. ‘I’m sure that checklist is on the minds of every mother struggling to make ends meet after finishing an eight-hour shift somewhere. She’s probably just relieved the kids didn’t kill each other.’
Kim had little time for perfect parenting checklists. For the most part, they were unrealistic, unachievable and managed only to make most parents feel inadequate.
‘I’m more interested in warning signs. Is there any kind of obvious escalation?’
‘Sibling rivalry is marked by elevated levels of hostility, resulting in delinquent behaviour, issues in adolescence, depression, anxiety, self-harm.’
‘That’s a big list,’ Kim acknowledged. And one they didn’t have time to work through. ‘But there’s one thing that still bothers me about this theory, which is that I get the sibling rivalry, I get the competitiveness of the examples you’ve used – but how often do these rivalries lead to murder?’
‘Chaw Cheng Hong, aged twenty-six, was stabbed to death by his twenty-three-year-old brother,’ Alison stated. ‘A seventeen-year-old boy in Karnataka recently stabbed his ten-year-old brother to death because he was jealous of—’
‘But that’s violence towards each other, not towards other people. Bring me some examples of—’
‘Boss, it’s probably nothing, but just thinking about what Alison said about career paths and all that.’
‘Go on,’ Kim said, turning to face Stacey.
‘Just looking at the details I dug up on Ella and Andrew Nock.’