The pregnant Gossip Girl star, 40, who has filed for divorce from Giersch, 34, is seeking to take Hermes to New York, where the show is filmed, until the end of March. Giersch strongly objects, calling her job detrimental to their son.
After almost two hours of testimony, no ruling was made and the hearing will resume Friday morning.
Giersh, a German entrepreneur, testified that Rutherford's "being on call in New York, working 20-hour days, her being told to go here, go there, jump into this car, go to this event," contributed to their failed marriage.
"Hermes doesn't feel comfortable in New York," he said. "He's in constant fear, not knowing what's going on. It's not easy there, it's not safe, it's noisy. As a father you see whether a child is comfortable or not."
Giersch described how he's been physically with his son "90 percent of the time," taking him to the playground, zoo, museums, and more, while Rutherford was working on Gossip Girl. "I don't see any reason to give a child to a caretaker when there's a better option, and that's the parent," he said.
Giersch added that Rutherford "has never allowed me to have overnights alone with Hermes. There are certain issues that she needs to [have] control."
Choosing Her Career or Her SonRutherford, wearing a black sweater, matching pants and gold earrings with her hair pulled back, took the stand next.
"If I'm being asked to choose my career over my son, I choose my son," she said. "[But] I need this job to pay my bills, legal bills, and Daniel has offered no support."
She denied that she was against overnights for Giersch, as long as a schedule was worked out first. "We can continue to co-parent as we have," she said.
Rutherford also took issue with Giersch pointing out her preoccupation with shopping, manicures and pedicures, saying, "It's not just me, I mean, he gets his eyebrows waxed."
Her testimony was cut short and the hearing will resume at 9 a.m.
The Best for the FamilyOutside of court, a smiling Rutherford said, "Ultimately I want the best for Daniel, and I want the best for our family."
Asked what keeps her going through an acrimonious divorce while carrying their daughter, she replied, "I think about the great love I have for this child. I try to not think [about the divorce] and instead think about my kids and my future ... and how lucky I am to be a mother at 40."
Giersch made no comment following the hearing.
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