"I catch myself all the time, like, 'Oh my God, I was just my mother,' "Jamie-Lynn Sigler, 34, tells PEOPLE. "Even my husband and my friends will be like, 'Whoa, you were just your mom right there.' "
Her mom Connie Sigler, 68, agrees: "She's very determined and likes to win an argument. And so do I!"
And when it comes to life's tougher moments, Jamie-Lynn, who is mom to 2-year-old son Beau with her husband Cutter Dykstra, says she turns to her "lookalike" mom for unwavering support.
"Sometimes I'm too independent, where I don't share what I'm going through," says the actress, who recently opened up about living with multiple sclerosis. "My mom and I have this crazy connection where if I'm not reaching out, she'll pick up the phone and say, 'I feel like you need me, what's going on?' She is a good reminder that it's noble to ask for help."
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The former Sopranos star revealed in January that she had been living with MS for 15 years.
"I can't walk for a long period of time without resting. I cannot run," she said at the time. "Stairs? I can do them but they're not the easiest. When I walk, I have to think about every single step, which is annoying and frustrating."
Although there is no cure for MS, Sigler said she had been able to keep her symptoms stable with the twice-daily pill Tecfidera.
"Things are manageable now," she said. "It takes a fighting attitude to deal with all this. This disease can absolutely take over your life if you let it."