The Newsroom actress, 42, and the comedian, 40, celebrated their boy's first birthday on Nov. 24 with a sweet gathering held in honor of the occasion.
"Just got back from celebrating ONE YEAR of the most joyful baby being in this world and in our lives," Olivia wrote on Instagram Nov. 27. "My son, my joy. Happiest Birthday Malcolm Hiệp! I love you so so so much."
During the festivities, Malcolm wore a crown with the number "1" in the middle that was knitted by Olivia's mom, Kim Munn. Meanwhile, Malcolm and John also sported coordinating white button-up shirts while Olivia donned a green dress and a birthday party hat.
And what's a birthday party without some delicious treats? Olivia also shared a video of the moment she and John presented Malcolm with a chocolate cake and how her mom ended up sticking a small bite in his mouth after growing "impatient" for him to try it.
"For what it's worth," the X-Men: Apocalypse star wrote on Instagram, "he did start eating the cake after that."
And it looks like he enjoyed the sweet treat as his white shirt was soon covered with chocolate cake. As Olivia wrote on Instagram Stories, "Birthday baby liked the cake."
So much so in fact that Olivia wondered if Malcolm said "I love you" for the first time while eating the dessert.
"If he is saying it," she wrote, "it's fitting that the first thing a child of mine would say 'I love you' to would be cake."
Olivia and John announced Malcolm's arrival on Christmas Eve last year, one month after his birth. Since then, the couple has continued to give glimpses into their life as a family of three. For instance, Olivia has posted adorable snapshots of the child, revealed his milestones like his first words and footage of him crawling and shared her postpartum journey. Malcolm also made a sweet cameo during John's comedy show in August and was seen in a photo for the comic's Saturday Night Live appearance in February.
"He has his whole life ahead of him. He hasn't even tried seltzer yet," John wrote in part of a December Instagram post announcing the birth. "I'm very in love with him and his whole deal."