https://www.dailymail.co.uk/news/article-13765351/Father-Trump-shooter-Thomas-Matthew-Crooks-hires-criminal-attorney.html
"The development comes as one family member shared with DailyMail.com that the FBI, 'still very much has questions' regarding how much the killer's parents knew – while revealing that his father Matthew Crooks, 53, is a gun enthusiast who has sold firearms to relatives in the past."