1st day of retirement: Olympic champion Micheal Phelps bonds in a pool with family

23-time gold medalist - Olympic swimming champion, Micheal Phelps, whose net worth is estimated to be $55 million, officially announced on Monday that he is retiring to focus on building a family with his fiancée Nicole Johnson, 31, and their three-month-old baby Boomer.

He shared a photo from his first day of retirement today, and is seen in a pool with family. He captioned the photo: "There's nothing like being back home! Great way to spend my first day in retirement!"