Elizabeth and Damian Hurley have a "twin-like telepathy".
The 58-year-old actress attributes her close bond with her son - whose father is late producer Steve Bing - with having been "a single mother of a single child" and the pair always confide in one another.
Elizabeth told Britain's HELLO! magazine: "When there are just two of you, there's less falling out and stomping off because there's not really anywhere to go. There's just us.
"We have completely separate lives in some ways, and there are, of course, private areas, but we've become a very strong team. For some things, we're each other's confidants; for other things, we're each other's best friends, the person the other one most wants to tell things to."
"When there are just two of you, there's less falling out and stomping off."
Her son added: "We have a twin-like telepathy, and I think that serves us very well. But the moment there's a clash, it's like you're arguing with yourself.
"If we're fighting, we'll suddenly interrupt ourselves mid-sentence and go: 'Oh my God, I forgot to tell you.'"
However, the pair don't discuss each other's love lives and Elizabeth would never introduce her son to a man she wasn't serious about, explaining they are both still close to her former boyfriend Hugh Grant and ex-husband Arun Nayer.
Elizabeth said: "Although we are close in a myriad of ways, that's not one of them.
"But I would think very carefully about bringing anyone into my life, knowing that it will cross over with Damian's life. I'd never jeopardise our family dynamic.
"I've never hung out with anybody who didn't have a positive influence on his life. Everybody I loved, and continue to love, has always loved Damian as much as they love me, I'm sure."
"And the people I've remained close to have always felt like my family. Now I guess there's only Hugh and Arun, and I love them both, and they both love Damian."
But the 'Strictly Confidential' director confirmed both he and his mother are currently in relationships.
He said: "We are seeing people at the moment, but we're both quite private.
"I've seen first-hand how devastating relationships in the public eye can become, and we've both made a decision that until somebody is incredibly serious, we're not going to speak publicly about who we're seeing."
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