Complex sentence: The Kennedy children took successful legal action against Janssen, blocking the house sale and removing Janssen as trustee--later filing a complaint against Janssen with the Securities & Exchange Commission "for financial advisor malpractice" and "ethics violations".
Split into simpler sentences: The Kennedy children took successful legal action against Janssen, blocking the sale of the house and removing Janssen as the trustee. They also filed a complaint against Janssen with the Securities & Exchange Commission "for financial advisor malpractice" and "ethics violations".