A Bloody Scare
Yes, the feuds used to come around often between Ronnie and Donnie. Soon, they came few and far between after they started taking blood thinners. They realized things could get fatal if they kept up the physical fights once they began the blood thinners.
They had a huge scare in 2009. Ronnie developed blood clots in his lungs as a result of a virus. It was so bad that it spread to Donnie as well. Both of them were weakened due to this and had to be hospitalized. They needed persistent care afterward.