Pharmacist Hayley Tomkins was found with stab wounds to her stomach when she was found inside her burning Mooroolbark home about 9pm last night.
Her 11-year-old son and eight-year-old daughter were found unconscious and suffering smoke inhalation.
The children were taken to hospital in a critical but stable condition. They are understood to be in intensive care.
Their father was not inside the home at the time but has spent the day at their side.
9News understands he was giving tennis lessons nearby when he returned home to find emergency services trying to save his family.
Police are investigating the circumstances surrounding the deadly blaze.
“Police are not looking for anyone else at this time,” Victoria Police said in a statement.
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