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.""

No, from what I can tell this is not Teddy Roosevelt Jr. This is a different one than the one who served with II Corps in North Africa and then onto France. That’s why I’m having trouble locking down if this guy is of any significance.
And just for the record, Teddy and Teddy Jr were the only father son pairing to LEGITIMATELY receive the Congressional Medal of Honor. Doug’s was a complete sham.
When war broke out in Europe, Ted's older sister, Alice Roosevelt, wife of Congressman Nicholas Longworth, helped organize and found the America First Committee. Rallies were held across the country with Ted Roosevelt, second only to Charles Lindbergh, as a favorite speaker. Advocating neutrality was a paradoxical role for the children of Theodore Roosevelt and it would not last long. Kermit maintained the tradition of early involvement by joining British forces in 1939, already at war with Hitler, two years before the attack on Pearl Harbor. Ted asked to be reactivated and was assigned to his old 26th Infantry. Four days after the Japanese attack, FDR promoted him to brigadier general. - All the Presidents' Children by Doug Wead
Interesting, and I didn't know that General Roosevelt had these America First connections. Also of interest was that Ted and his younger brother Kermit were the first Westerners to confirm the existence of the Giant Panda.