A YOUNG mother sobbed after a Perth Supreme Court judge told her she won't be jailed for the accidental stabbing death of her baby daughter.

PerthNow reports that Nicole Frances Bryan, 23, of Dawesville, pleaded guilty to the manslaughter of her 16-month-old daughter Chenelle in March last year.



The WA Supreme Court was told today that Bryan, who had been a victim of serious domestic violence, had intended to scare her partner with a long-bladed kitchen knife, but when she attacked him she stabbed her daughter who was in his arms.



Justice Stephen Hall told Ms Bryan: "This is something that you will live with forever,'' and that her daughter's death was "an insurmountable tragedy''.



He imposed a two-year jail sentence, which he suspended for two years.



Bryan cried and sobbed continuously through today's hearing and thanked the judge after the sentence was passed.



Justice Hall said in the month leading up to the tragedy Ms Bryan had felt "trapped and helpless'' in a violent relationship with her partner.



"History does not justify or excuse your actions, but it does explain them,'' Justice Hall said.



Earlier her lawyer Michael Clarke told the court Ms Bryan targeted her de facto partner but did not intend to harm her daughter when she attacked him with a long-bladed kitchen knife.

Mr Clarke said his client had been caught up in a cycle of escalating domestic violence for four years with her de facto, who was now in jail for assaults against her.

Mr Clarke said Ms Bryan had been hopeful the pair's relationship might survive.

But they had started arguing on the way home from a social outing, at which Ms Bryan had taken off her jacket to reveal bruises, allegedly inflicted by her partner.

"He didn't want his friends to see his handiwork,'' Mr Clarke said.

After arriving at the couple's home Ms Bryan attempted to call a crisis line but was prevented by her partner, who allegedly stabbed her in the hand with a skewer.

Ms Bryan then picked up a knife, unaware Chenelle was in her father's arms, stabbing her in the chest cavity as he turned, Mr Clarke said.

"Ultimately she was lashing out at her de facto ... it all went horribly wrong,'' he said.

"She was completely unaware he was holding the child. She was completely unaware the child was in the kitchen, let alone in his arms.''

Prosecutor Michelle Ridley said the submission was difficult to accept and it was highly unlikely Ms Bryan did not know the baby was in her partner's arms.

Mr Clarke said Ms Bryan had been in custody since the offence and nothing would be achieved by her spending more time in custody.

Read more about the mum who accidentally stabbed her toddler at PerthNow