George Pimentel/Getty Tom Brady and Gisele Bundchen
Gisele Bündchen posted a birthday message to her Instagram story on Sunday, honoring her sister, Graziela Nonnenmacher Bündchen.
“Happy birthday to a true angel on earth! I love you so much sister!” the message, translated from Portuguese, said.
The photo shows Bündchen’s sister Graziela in blue giving the Brazilian supermodel, 42, a hug while Gisele makes a funny face with one leg up. Gisele used Instagram stickers to make it look like she was holding a birthday cake and added animated hearts to the photo.
The anniversary message comes as sources tell PEOPLE that Bündchen and Brady “have reached a rough patch” in their marriage.
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Brady and Gisele – who share son Benjamin Rein (12) and daughter Vivian Lake (9), along with quarterback son John “Jack” Edward, 14, whom he shares with ex Bridget Moynahan – have been married for 13 years after they split. met through friends. The couple tied the knot a month after they got engaged in an intimate ceremony on February 26, 2009 at St. Monica Catholic Church in California.
Sources have revealed to PEOPLE that the pair are in disagreement over the Tampa Bay Buccaneer’s quarterback decision to play another season in the NFL — a choice that has led to “a lot of tension” between the longtime pair.
During Labor Day Weekend, Brady and Gisele seemed to spend time apart. Sources told PEOPLE that the supermodel took Benjamin and Vivian to a Florida water park, while Brady flew to New York to watch his son Jack’s soccer practice.
Gisele “wasn’t happy” with her husband’s decision to retire from professional football earlier this year after just two months, a source close to Brady told PEOPLE.
“They are coming to a difficult point,” the insider continued. “But I know they’re trying, or at least he’s trying, to find out and make it work. He wants to get through this and make things better.”
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A source with the Buccaneers told PEOPLE that no preparations are being made for Gisele to attend her husband’s first game of the season, which takes place on Sunday.
“It’s always a big party when Gisele comes to watch the game, [but] from now on there will be none of that for Sunday’s game,” the source said.
“It feels very different this year from last year. She was excited to be here, we saw her around,” the source continued. “I’m not saying it’s impossible for her to come, but there’s no place for her to be here for the first game of the regular season and that seems weird.”
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The insider added that people are not raising Gisele around Brady.
“Everyone here knows there is tension, but we don’t know how serious it is. So we just don’t talk to him about Gisele. It’s not a topic anyone wants to bring up.”
Rumors of a split between the pair rose after Brady was released from practicing with the Buccaneers last month “to handle some personal stuff,” head coach Todd Bowles said at a news conference at the time. According to Bowles, Brady and the team discussed the absence before the start of training camp in July.
RELATED: Tom Brady and wife Gisele Bündchen ‘hit a rough patch’ in marriage: ‘There is a lot of tension’
Brady spoke of his absence from the team after eventually returning 11 days later.
“Everyone has different situations they face and we all have unique challenges in our lives,” Brady told reporters. “I’m 45 years old, man.”
“There’s a lot of s- going on, so you just have to try and figure life out as best you can. You know, it’s an ongoing process,” he continued.