Boomer, Beckett and Maverick are getting a brother or a sister.
Michael Phelps and his wife Nicole Johnson announced on social media that they will soon become the parents of four children.
They’ve been married since 2016 and have three sons — Boomer, 7, Beckett, 5 and Maverick, 3, People reported.
Johnson shared several photos on Sunday to mark their wedding anniversary.
They haven’t announced the gender of the baby, but one commenter noticed that the hearts she used were blue and asked them if they were expecting another boy.
Phelps earned 23 gold, 3 silver and 2 bronze medals over his Olympic career. He is the most decorated Olympian of all time after competing in 2000, 2004, 2008, 2012 and 2016.
Through the years 18 Sep 2000: Michael Phelps of the USA in action during the Mens 200m Butterfly Heats at the Sydney International Aquatic Centre on Day Three of the Sydney 2000 Olympic Games in Sydney, Australia. \ Mandatory Credit: Ross Kinnaird /Allsport (Ross Kinnaird/Getty Images)
Through the years 24 JUL 2001: L-R Tom Malchow and Michael Phelps of the USA pose with their Sivler and Gold medals after the Mens 200m Butterfly at the Marine Messe Pool during the World Swimming Championships, Fukuoka, Japan. DIGITAL IMAGE. Mandatory Credit: NickWilson/ALLSPORT (Nick Wilson/Getty Images)
Through the years YOKOHAMA- AUGUST 25: Michael Phelps from the USA swimming in the 400m individual medley heats during the 2002 Pan Pacific Swimming Championships at Yokohama swimming pool in Yokohama, Japan on August 25, 2002. (Photo by Sean Garnsworthy/Getty Images). (Sean Garnsworthy/Getty Images)
Through the years NARBONNE, FRANCE - JULY 15: Michael Phelps of USA practices for the 2003 World Swimming Championships at the USA Team Training pool on July 15, 2003 in Narbonne, France. (Photo by Al Bello/Getty Images) (Al Bello/Getty Images)
Through the years NARBONNE, FRANCE - JULY 15: Michael Phelps of USA practices for the 2003 World Swimming Championships at the USA Team Training pool on July 15, 2003 in Narbonne, France. (Photo by Al Bello/Getty Images) (Al Bello/Getty Images)
Through the years BARCELONA, SPAIN - JULY 22: Michael Phelps of the USA celebrates setting a new World Record in the Men's 200m Butterfly Semi-Final during the 10th Fina World Swimming Championships 2003 on July 22, 2003 at Palau Sant Jordi in Barcelona, Spain. (Photo by Al Bello/Getty Images) (Al Bello/Getty Images)
Through the years BARCELONA, SPAIN - JULY 27: Michael Phelps of the USA stands with his six medals won during the 10th Fina World Swimming Championships 2003 at Palau Sant Jordi on July 27, 2003 in Barcelona, Spain. Phelps won gold while setting world records in the 200m Butterfly, 200m Individual Medley and 400m Individual Medley with gold in the 4x100m Medley Relay while winning silver in the 4x200m Freestyle and 100m Butterfly. (Photo by Shaun Botterill/Getty Images) (Shaun Botterill/Getty Images)
Through the years SYDNEY, AUSTRALIA - NOVEMBER 26: Michael Phelps of USA launches off the blocks at the start of the Men's 200m Middle Distance freestyle race during the Qantas Skins Swim Meet at the Sydney Olympic Park Aquatic Centre November 26, 2003 in Sydney, Australia. (Photo by Daniel Berehulak/Getty Images) (Daniel Berehulak/Getty Images)
Through the years MELBOURNE, AUSTRALIA - NOVEMBER 29: Michael Phelps of the USA in action during the Mens 200m Backstroke during Finals on day two of the FINA World Cup Swimming Championships held at Melbourne Sports and Aquatic Centre, November 29, 2003 in Melbourne, Australia. (Photo by Ryan Pierse/Getty Images) (Ryan Pierse/Getty Images)
Through the years ATHENS - AUGUST 19: Gold medalist Michael Phelps of USA celebrates on the podium during the medal ceremony of the of the men's swimming 200 metre individual medley competition on August 19, 2004 during the Athens 2004 Summer Olympic Games at the Main Pool of the Olympic Sports Complex Aquatic Centre in Athens, Greece. Ryan Lochte of USA came second and George Bovell of Trinidad came third. (Photo by Al Bello/Getty Images) (Al Bello/Getty Images)
Through the years BEIJING - AUGUST 11: (L-R) Garrett Weber-Gale and Michael Phelps of the United States celebrate finishing the Men's 4 x 100m Freestyle Relay Final in first place to win the gold medal held at the National Aquatics Center on Day 3 of the Beijing 2008 Olympic Games on August 11, 2008 in Beijing, China. The United States finished the race in first place in a time of 3:08.24 and wins the gold medal and set a new World Record. (Photo by Cameron Spencer/Getty Images) (Cameron Spencer/Getty Images)
Through the years BEIJING - AUGUST 13: (L-R) Silver medalist Laszlo Cseh of Hungary, gold medalist Michael Phelps of the United States and bronze medalist Takeshi Matsuda of Japan stand on the podium during the medal ceremony for the Men's 200m Butterfly at the National Aquatics Centre during Day 5 of the Beijing 2008 Olympic Games on August 13, 2008 in Beijing, China. (Photo by Nick Laham/Getty Images) (Nick Laham/Getty Images)
Through the years BEIJING - AUGUST 16: Michael Phelps of the United States celebrates victory in the Men's 100m Butterfly Final held at the National Aquatics Centre during Day 8 of the Beijing 2008 Olympic Games on August 16, 2008 in Beijing, China. By winning gold in the Men's 100m Butterfly Phelps tied Mark Spitz's record of winning seven gold medals in a single Olympic Games. (Photo by Shaun Botterill/Getty Images) (Shaun Botterill/Getty Images)
Through the years BEIJING - AUGUST 17: Michael Phelps of the United States smiles with the American flag as he wears his eighth gold medal after the Men's 4x100 Medley Relay at the National Aquatics Centre during Day 9 of the Beijing 2008 Olympic Games on August 17, 2008 in Beijing, China. (Photo by Adam Pretty/Getty Images) (Adam Pretty/Getty Images)
Through the years ROME - AUGUST 01: Michael Phelps of the United States celebrates victory in the Men's 100m Butterfly Final during the 13th FINA World Championships at the Stadio del Nuoto on August 1, 2009 in Rome, Italy. Phelps broke the world record setting a new time of 49.82 seconds. (Photo by Al Bello/Getty Images) (Al Bello/Getty Images)
Through the years RIO DE JANEIRO, BRAZIL - AUGUST 05: Michael Phelps of the United States carries the flag during the Opening Ceremony of the Rio 2016 Olympic Games at Maracana Stadium on August 5, 2016 in Rio de Janeiro, Brazil. (Photo by Clive Brunskill/Getty Images) (Clive Brunskill/Getty Images)
Through the years NEW YORK, NY - NOVEMBER 21: Michael Phelps, wife Nicole Johnson and their son Boomer arrive to the 2016 Golden Goggles Awards at the Marriott Marquis Hotel on November 21, 2016 in New York City. (Photo by Jeff Zelevansky/Getty Images) (Jeff Zelevansky/Getty Images)
Through the years LOS ANGELES, CA - NOVEMBER 19: Presenters Michael Phelps and Kobe Bryant announce the winner of Female Athlete of the Year during the 2017 USA Swimming Golden Goggle Awards at J.W. Marriott at L.A. Live on November 19, 2017, in Los Angeles, California. (Photo by Kevork Djansezian) (Kevork Djansezian/Getty Images)
Through the years SCOTTSDALE, ARIZONA - FEBRUARY 10: (L-R) Nicole Johnson and Michael Phelps attend Shaq's Fun House Big Game Weekend at Talking Stick Resort on February 10, 2023 in Scottsdale, Arizona. (Photo by Ethan Miller/Getty Images) (Ethan Miller/Getty Images)
Through the years MADISON, WISCONSIN - JUNE 10: Former Olympic Swimmer Michael Phelps of the United States plays his tee shot on the 10th hole during the Celebrity Foursome at the second round of the American Family Insurance Championship at University Ridge Golf Club on June 10, 2023 in Madison, Wisconsin. (Photo by Patrick McDermott/Getty Images) (Patrick McDermott/Getty Images)
Through the years PHOENIX, ARIZONA - OCTOBER 21: Swimmer Michael Phelps throws out the ceremonial first pitch prior to Game Five of the Championship Series between the Philadelphia Phillies and the Arizona Diamondbacks at Chase Field on October 21, 2023 in Phoenix, Arizona. (Photo by Sean M. Haffey/Getty Images) (Sean M. Haffey/Getty Images)