The couple separated in January after seven years of marriage. Klum later filed for divorce, with Seal counter-filing shortly after.
Radar Online now reports that while the terms surrounding the split were intended to be amicable, tensions have arisen over issues surrounding the pair's four children and their financial assets.
The site reports that Seal contests Klum's claims that they had no joint assets to be divided. Seal is said to be worth $15 million, while Klum's net is approximately $70 million.
It is also claimed that Klum was unhappy with Seal's decision to use candid photos of their kids in an ad campaign for a Leica digital camera without asking her permission first.
"Heidi isn't trying to cause trouble," a source said. "She's just trying to protect her brood. Since she filed for divorce from Seal, he's been out with more than one young woman, whereas Heidi hasn't dated at all."
The insider added that the supermodel and Project Runway star has no interest in dating, adding: "She's not interested in beginning another relationship right now. Her primary goal is getting the kids through the divorce and making sure they are healthy and happy."
Klum recently confessed that she is unsure if she will marry again in the future.