In the snap, the dad-to-be holds up an ultrasound photo and, adorably, Caiden has his sweater pulled up and is gazing down at his own belly.
“BOOM! Baby number 2! Can’t wait to bring my fam of 4 to #tokyo2020,” Lochte, 34, captioned his post, while Reid wrote alongside hers, “We are SO SO EXCITED! Baby #2. We can’t wait to meet you already!” and shared that the new addition was due in June.
The couple tell PEOPLE exclusively, “Caiden is hands down the best part of our lives, so we can’t wait to grow our family together and watch him become a big brother!”
Lochte and Reid, 27, celebrated their marriage in September during an intimate outdoor wedding at Morrow Ranch in Palm Springs, California, exchanging vows in front of 100 of their closest friends and family.
Caiden served as ring bearer, and the newlyweds told PEOPLE that part of the reason they waited so long after their October 2016 engagement to tie the knot was so that their son could be part of their big day.
“Since we had Caiden, we both wanted him to be a part of [our wedding] in some way,” said Lochte.
“We wanted Caiden to be old enough to walk down the aisle,” added Reid. “One of our visions was to have him be able to be the ring bearer, so it’s perfect timing!”
The baby news couldn’t come at a more perfect time. Shortly after their September wedding, the spouses opened up to PEOPLE about their desire to expand their family sooner rather than later.
“Since I met [Kayla], I’ve always wanted two kids before 2020 Olympics so it will be perfect if we get pregnant before 2019,” said the soon-to-be father of two.
Added Lochte, “I wanted boy, girl and then maybe talk about three [kids]. But if we get boy, boy, then [we’ll] try to go for a third one.”