A pregnant Montagu mother has been sentenced to 30 years behind bars for murdering her three-year-old daughter.Karen Isaacs, 30, in a plea agreement confessed to throttling Kay-Leigh Isaacs, as well as abusing her little girl, the Western Cape High Court heard on Tuesday. She has three other children, aged 7, 10 and 15.In her explanation, Isaacs said she had murdered the child because she was worried that there would be "no one to look after her" if a fellow farmworker killed her and her ill, common-law husband.The farmworker, she said, had made sexual advances towards her, and had referred to her children as his.She had not entertained his advances, which "made him aggressive".According to Isaacs, the man would break windows and doors and threaten her and her common-law husband, who was physically unable to chase him away.Neighbours would often intervene, she said.When she woke up on March 16, she started drinking. Later that morning she took Kay-Leigh to a secluded part of Bloufontein Farm, where she choked her to death, Isaacs confessed.She left Kay-Leigh's body there and went to drink with a friend.Kay-Leigh was reported missing four days later. Isaacs had told the police that her daughter was visiting family, but on their way there, she admitted to killing her daughter, pointing out where her decomposing body could be found.Isaacs had admitted abusing the little girl and ill-treating her by swearing, pulling at her, threatening to kill her and being drunk while the child was in her care.In 2018, Isaacs' children were placed in temporary safe care. When the order lapsed, Kay-Leigh was returned to her mother.In addition to the 30-year sentence for the murder, Isaacs was also handed a six-month sentence for the abuse charge.