angus hawley 's brother said his late sibling ` did n't have heart problems '
he is reported to have had a suspected heart attack in new york .
angus was a father of four children - lucia , hamish , james and sybella .
he had all four with nicole kidman 's sister antonia before their 2007 split .
both 44-year-old antonia and angus , 46 , remarried following their divorce .
angus ' death comes seven months after dr. antony kidman 's death .
nicole and antonia 's father also died of a heart attack in singapore .