what she had was charisma. she said i love you and in my heart i knew those were her last words. two sisters with a single purpose, solved the mystery of their mother s death. we cannot let this go. she left for hawaii, a new life with a new husband but the sunny paradise soon grew dark. something is very wrong. it was horrible being so helpless. what was behind their moms death? they set out together to get some answers and they were about to get some help from their mother herself. a possible clue hidden in a envelope marked baby pictures, tucked inside a journal that painted a different picture entirely. i pulled out that envelope. reporter: could their mom help them solve their own mystery? we are her boys. we made a promise to our mom. hello and welcome to dateline. charlene was popular and unpredictable long before she had her girls kenny and tiffany. as children they adored their mother, as adults they made a troubling vow, promising charlene to i