A President.
"Old Whitey" was the war horse he kept at the White House.
The name of Jackie Kennedy's horse at the White House was "Sardar." Jackie Kennedy rode Sardar on the grounds of the White House and during public events.
Wilson
You are likely thinking of Taft who kept a cow in the White House in order to have fresh milk .
According to the related link below, he kept a parrot / macaw in the White House.
Zackary Taylor
Taft kept a cow on the white house grounds in order to have fresh milk.
yes he had horses in the White House
I think it was Teddy Roosevelt.
Calvin Coolidge
Calvin Coolidge
when you get your first horse in the registration process, you can choose it's colour. If you want more white horses, then buy some at the auction house.