Leo allows himself a small smile. The meaning behind his brother's words isn't lost on him, and more than anything, he appreciates Don looking out for him. Leonardo is just thankful that he's filled in what blanks nestled across that one-year timespan he could.

"Keep me updated on the radio system." He leans back forward and starts lining up the chess pieces. "Otherwise... I'll let you get back to your icebox."

It may be a dismissal, but there's a teasing edge to it that should say everything he doesn't.