On this week’s Parenting segment, one listener is unsure how to proceed with a toddler who won't stop hitting her sister on the head.

"Our toddler regularly bangs her one-year-old sister on the head," they told Moncrieff.

"She does this if she wants a toy she has, or even if there's no apparent reason at all.

"We've tried multiple techniques to deal with this, including writing a big sign on the wall that says, 'I must not hit my sister on the head'.

"We bring her over to the sign each time and she reads it out and seems to think it's hilarious.

"How do we get her to stop doing this and be gentle with her sister?"

Impulsive

Child psychotherapist Dr Joanna Fortune said no matter how much the child's parents try to encourage her to respect the sign, a three-year-old will struggled to understand.

"That highly impulsive behaviour is very developmentally appropriate at her age, that capacity for reflective functioning and cause and effect thinking – that is not there at all," she said.

"I think you have to tell her what you want her to do, rather than what you don't want her to do.

"If you want to put a sign up, let it say 'I must play nicely with my sister, or I am kind to my sister or I play well with my sister', other language that is pointing her in the direction of what you want to elicit from her rather than what you don't."

Toddler having a temper tantrum (Leila Cutler / Alamy Stock Photo)

Dr Fortune said it is most important to remember how young the child really is.

"All the signs in the world – she's three years old, " she said. "So, show her what you want rather than telling her what you want."

"When she hits her sister on the head, you're coming over, you're taking her hands and you're coming down to her eye level.

"Acknowledge what's going on; 'We don't hit in this family, and when you want to hit, hit the cushion.'"

"Show her what you want her to do and you will repeat that over and over and over because she's three.

'Impulse control'

Dr Fortune recommends introducing impulse control games.

"Impulse control play looks like stop-start games, things like Mother May I?, Simon Says, red light green light,' she said.

"Waiting for the cue of somebody in charge to say when you can go or not is a really healthy way to play with that high impulsivity.

"I wouldn't psychopathologise because three-year-olds are impulsive little people."