A heartbroken mother has paid tribute to her "beautiful" daughter who died three years after the sudden death of her big brother. Alexander Cooper was just three when he died suddenly after being "a bit unwell" on Boxing Day 2021. On Thursday his sister Isabelle also lost her life less than a year after discovering she had the same rare genetic disorder as her brother.

Posting on X, formerly Twitter , her mother Dr Emily Cooper, a lecturer at the University of Central Lancashire in Preston, wrote: "We are devastated to say that our beautiful Isabelle died in the early hours of this morning. "We are absolutely broken. However, we want you all not to think of her death, but to honour her by living life as she did: fearlessly, joyously & spontaneously.

" Alexander's death was "unexplained" for almost two years after there had been few signs anything was wrong. The three-year-old had celebrated Christmas the day before and his family told how he had been perfectly fine. He had spent Christmas Day opening presents and had been dancing with his little brother Freddie, then two, to the Masked Singer.

The following day Emily had taken Freddie for a walk and returned home to find emergency services outside the house. Alexander was taken to hospital but died later that evening. Following his death his devasted parents began to raise awareness of sudden deaths in children helping the charity Sudden Unexplained Death in Childhood UK.

The family was left with no answers for the cause of hi.