"The kids love Tom," the insider tells PEOPLE. "He is a great dad."
Following weeks of a rumored rift in their marriage, both Bündchen, 42, and Brady, 45, have enlisted divorce lawyers, PEOPLE has confirmed, and the supermodel has been working with hers for "awhile," a source previously added.
"She feels bad for the kids," the source adds of Bündchen.
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Dimitrios Kambouris/Getty Tom Brady and Gisele Bündchen
Earlier this week, the model was spotted in Miami going to the gym with daughter Vivian and son Benjamin. In photos obtained by TMZ, Bündchen and her two kids were dressed in casual attire while out in South Beach.
Gisele Bundchen Instagram
Meanwhile, Brady's team, the Tampa Bay Buccaneers, had a home game last Sunday and will face off against the Atlanta Falcons in Tampa this weekend.
Although the children were not spotted at Brady's last home game, Vivian, Benjamin and Jack cheered on their father in the Buccaneers' home opener the previous week.
Douglas P. DeFelice/Getty Images
"Football is such a big draw to him," a source previously told PEOPLE in September. "Something's got to give, and it has always been his family. They have to be so patient for him."
In an interview this summer with Elle, Bündchen said that she has her "concerns" about Brady continuing to play, especially when it comes to their kids.
"Obviously, I have my concerns — this is a very violent sport, and I have my children and I would like him to be more present," the Brazilian model said. "I have definitely had those conversations with him over and over again."
"But ultimately, I feel that everybody has to make a decision that works for [them]. He needs to follow his joy, too."