Are the ‘terrible twos’ a consequence of sibling rivalry?

Whilst conversing about our children and the dreaded ‘terrible twos’, one of my mummy friends posed an interesting theory (something that she had read somewhere):

That the so-called ‘terrible twos’ is a consequence of sibling rivalry; it’s a function of the fact that parents often have a second child at around this age.

What this means is that the tantruming exercised by a large percentage of the world’s two-year-old population is more behavioural than developmental.

Perhaps you’ve heard this theory before? Google wasn’t helpful in unearthing any studies or scientific proof for such an idea. That said; it does make sense.

When another baby is thrown into the family dynamic, the already existing sibling(s) of said baby is in for a bit of shell shock.

Mum and dad’s undivided attention suddenly becomes divided – very divided. It’s a tough pill to swallow – especially for a two-year-old coming to terms with her emotional content.

Okay so, how your pre-schooler will react to a new baby does depend on temperament. Some children are more chilled by nature and will most likely adjust easier to the new dynamic but for kids who are highly-strung, coming to terms with a new baby can be a real challenge.

When your two-year-old feels insecure, and consequently out of control, she’ll act out; often with aggressive behaviour, roaring tantrums – you’ll probably be surprised at how creative your child can be in performing her woes.

As your child becomes more self-aware and starts to negotiate her place in the world, as well as establish come control over her environment, she’s bound to lose the plot on the occasion.

A new baby will exacerbate an already delicate situation. Sounds like a bit of nature/nurture, doesn’t it? In other words developmental as well as behavioural.

Theory debunked?