"Happy late Thanksgiving to everyone", the 24-year-old wrote, alongside a bucolic photo of a snowy late-Autumn treescape. "First time both sides of the family has come together", he wrote.
He reflected further, writing: "Every day is a learning process, trying to be more like him, patient, kind, selfless, boy I got a long way!"
"My heart is COMPLETELY and FULLY YOURS and I will ALWAYS put you first!" The group also celebrated Thanksgiving.
Not only was it Thanksgiving but the Biebers were also celebrating Hailey's 22nd birthday, making it a double whammy for the new family.
Pattie took to social media to wish her daughter in law a wonderful birthday and also used this opportunity to show the world just how much she loves her!
It's the first time he's confirmed he's married to Hailey Baldwin.
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Khachanov recorded his third straight Top 10 win at the Paris Masters after shocking John Isner and Alexander Zverev . Open. "I'm a little bit upset about the whole situation because this is not how I wanted it to end".
"HAPPY BIRTHDAY @haileybaldwin! I LOVE YOU!"
She certainly feels part of the family.
The couple were rumoured to have married in a NY courthouse two months ago, but Hailey Baldwin denied it at the time.
There were reports that the pair had a secret ceremony around the same time, but the couple didn't comment.
Hailey's father Stephen Baldwin was present for his daughter's big day, as well as Justin's mom Pattie Mallette and her cousin Kahlea Baldwin, who both posted pictures and videos from the cover girl's B-day bash. After she blew out her candles, Justin gave a brief speech about her, with Mallette, capturing a few seconds of it on her Stories: "Happy birthday to the love of my life", the singer said in the video. A source told People that his decision to take a break is proving to be an adjustment for the pop superstar - but not an entirely unpleasant one.
The source added, "It's a very mature thing to do". She encourages him to do whatever he wants to do, and is encouraging him in this season of self-discovery. "I see no reason to wait".