Photograph shows 6ft 4" Michael Phelps towering over 4ft 8" Simone Biles

Little and large: 6ft 4" Michael Phelps towers over 4ft 8" Simone Biles in photo that shows the height difference between America's Olympic stars.

-Michael Phelps is 31, stands at 6ft 4" tall and has won 28 Olympic medals
-Simone Biles is just 19, 4ft 8" and won her third gold medal Sunday night 
-He was in rehab last year and she was put up for adoption aged six
-Each faced hurdles, but they are now America's biggest Olympic stars
-Biles uploaded a photo of the pair showing the height difference

6ft 4" Michael Phelps towers over 4ft 8" Simone Biles in Twitter photo

Michael Phelps is 31 years old, stands at 6ft 4" tall and has won 28 Olympic medals during his long swimming career.  Simone Biles is a newbie to the Games at just 19, is 4ft 8" and won her third gold medal Sunday night.
He was in rehab for substance abuse last year and she was put up for adoption when she was only six year's old because her mother's drinking and drug use. 
Despite their vastly different back stories and physical attributes - demonstrated in a hilarious photo of Phelps towering over Biles which she posted on Twitter earlier this week -  they are now America's biggest Olympic stars, albeit at opposite ends of their respective careers.