Rose Marie, who’s already achieved what’s been called “the longest career in show business,” is still plugging along with “Wait for Your Laugh,” an upcoming documentary about her life directed by Jason Wise.

The onetime child singer, who turns 94 on Tuesday, was born Rose Marie Mazetta in New York City. She shot to fame as late-1920s radio star “Baby Rose Marie,” was the opening act (with pal Jimmy Durante) at Bugsy Siegel’s Flamingo Hotel in Las Vegas in 1946, and co-starred on Broadway with Phil Silvers in “Top Banana” and then as wisecracking comedy writer Sally Rogers on “The Dick Van Dyke Show” along with Van Dyke, Mary Tyler Moore, Morey Amsterdam and Carl Reiner. Later, she joined “The Doris Day Show” and was a longtime regular on “Hollywood Squares” in the 1970s.

Here, Rose Marie talks about her remarkable life, including her interactions with Al Capone (whom she called “Uncle Al”) and Marlon Brando.

How did you meet Al Capone?

I was working at the Palace Theater in Chicago with Milton Berle. I must have been 10 or 11. My father traveled with me and the doorman [at the theater] told my father there was a man outside who wanted to see him. It was Al Capone. This big limousine was there and this man said, “Hi, Happy” — my father had a nickname, Happy Hank — “we want to see your kid. The boys love her and want to meet her. I want you to come over to the house for dinner.” I kept looking at my father like, who the hell is this? The next day a limousine picks me up about 4 p.m. and we drove to Cicero and went into a house. There was this long, long table, in the living room, with about 24 chairs and these guys are sitting around there and they all wanted to meet me. They all gave me a hug and a kiss and said, “We think you’re wonderful, you take care of yourself, Baby” — everyone called me “Baby” at that time — and Al Capone picked me up in his arms and said, “Anything you want and anything you need, you let Uncle Al know — and you call me Uncle Al from now on.”

Did you ever need a favor from him?

Oh, a couple of times (laughs).

What was your relationship with Mary Tyler Moore on “The Dick Van Dyke Show”?

We were friendly enough but we weren’t very close. Mary knew the minute she did the show how her life was going to be; she wanted to be a big star and she accomplished that. Mary was an artist as far as all of us were concerned because I was like one of the boys — Morey and Carl and [producers] Danny Thomas and Sheldon Leonard, they always fit me into their group. Mary was strictly feminine, beautiful and young and everyone made a play for her. When we did “The Dick Van Dyke Reunion Show” [in 2004] we got to be very close, and we said to each other that we wasted a lot of time not being that close. So now and then we would write a note, and whenever she came here [to LA] we would go out to lunch.

What’s been the highlight of your career?

That’s a very hard question. I’ve had many ups. I did a Broadway show with Phil Silvers called “Top Banana” and I stopped the show, twice, on opening night. Marlon Brando came up to me at a party afterwards and said, “I saw the show tonight. F–k everyone, you were great,” and he kissed me on the cheek. All the wonderful people I’ve worked with — Milton Berle, Phil Silvers, Dick [Van Dyke], Carl, Sheldon, Danny … with people like that, how can you go wrong?

Tell me about opening The Flamingo in 1946

The owner of the Hollywood Reporter came to see me when I was working at Slapsy Maxie’s, which was the nightclub here [in LA], and said, “Do you want to play Vegas?” I said, “What’s Vegas?” I know on my honeymoon we drove through Vegas; it was nothing but sand and only two hotels, The El Rancho and The Last Frontier, all cowboy kind of places. I was going do a new show [at The Flamingo] with Jimmy Durante and Xavier Cugat. I was very close to Jimmy and [his wife] Marge; Jimmy would always show me how to imitate him and I would do some of that in my act. I had Durante numbers written by Jimmy. So we went to Vegas and there was this fabulous place called The Flamingo. It was like Monaco, with neon and everything and was so out of place with the other hotels. There were no rooms and we all stayed at the El Rancho. Our opening night, all the stars from Hollywood came — Clark Gable, Robert Taylor, Barbara Stanwyck, Lana Turner, we were jammed opening night and the show was fabulous. Xavier [Cugat] was the orchestra leader, Tommy Wonder was the dancer and then I would come on and do my act. Then Jimmy would come on and do his act, then I would come back out, imitating him, and he would say, “Wait a minute, there’s an impersonator here and I don’t know who it is,” and we would do two Durantes and I would wind up singing with him and doing the walkoff with him. It was the greatest show in the world but only lasted two nights because the stars went back after the second night and the locals were afraid of The Flamingo. We worked to nine people the third night because everyone was afraid of this monster in the desert.

You knew Morey Amsterdam from vaudeville, right?

I knew Morey from the time I was 11. When I was doing my nightclub act, Morey wrote all my material. He was very well known in show biz as a comic and an actor, and when I recommended him for “The Dick Van Dyke Show,” he became world-famous, which is what he deserved. He was brilliant as a writer and brilliant at being funny. He was called “The Human Joke Machine.”

What about Doris Day?

She is the sweetest person in the world. We became very, very close. The way you see Doris is the way she really is. We talk about once a month on the phone.