I was trying to figure out who this Colonel Theodore Roosevelt is, but cant really find much on him. It doesn’t appear he is related to the current President or the former one either.
Theodore Roosevelt, Jr.
""Roosevelt would be the only general on D-Day to land by sea with the first wave of troops...
""...Theodore Roosevelt, Sr., and Theodore Roosevelt, Jr., are one of only two sets of fathers and sons to have been awarded the Medal of Honor. The other set is Arthur and Douglas MacArthur.""

Porbably refers to TR’s son, Deputy CG of 1st ID with Terry de la Mesa Allen Div CG. Both rain afoul of Omar Bradley in Sicily. Roosevelt landed on the beaches with another unit on D-Day, where he died, either then, or shortly after.