The pregnant 37-year-old actress accused the 38-year-old former NFL player of infidelity in an interview with "Entertainment Tonight" after Hartwell unexpectedly filed for divorce and requested a paternity test this week.
"I have never cheated on him during my marriage. That's not who I am," Pulliam asserted. "[The paternity test is] not an issue. There's no problem. I've never been unfaithful to my husband. This is his daughter."
"I was ready to leave [when I found out he cheated]," she said. "I had divorce papers ready. I presented them to him. He said, 'Please, I want my family,' all of the right things. Once I was pregnant, I did decide to give him that one last chance."
Hartwell filed for divorce Monday in Atlanta, just a week after Pulliam announced she's expecting their first child.
The actress said she was blindsided by the news and admitted the sudden turn of events was hurtful.
"The part that hurt me the most when he filed for divorce was that he had asked me to give him another chance, and I was willing to do that and forgive him, for our family," she shared.
A source told People Hartwell wants a paternity test because Pulliam got pregnant during "a very dark spot" in their relationship. The insider said the former NFL player "doesn't have any evidence" the actress actually cheated.
Pulliam is best known for playing Rudy Huxtable on the NBC sitcom "The Cosby Show." She has since appeared on Tyler Perry's "House of Payne" and competed on "The Celebrity Apprentice" Season 7.
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