Frankie Grande says he needed a sober coach when he first quit drinking, saying the coach “stared at me for 90 days” to keep him away from alcohol.

TheBig Brotheralum, 42, looked back on his sobriety journey during a Wednesday, Dec. 3 appearance onUntraditionally Lalaafter host Lala Kent asked how he navigated sobriety and the alcohol-fueled world of reality TV.

“I got sober with a sober coach two years before I went onBig Brother(in 2014). It was a challenge for my therapist to see if I could do ninety days clean. And I was like, ‘Of course I can. That’s so easy,’” the older brother of Ariana Grande said. Meanwhile, “I couldn’t make it one day clean.”

That’s when Grande hired a sober coach, whom he said “stared at me for 90 days, and I did my 90 days clean. And at the end, I was like, ‘Work. See? That wasn’t difficult at all.’ Meanwhile, I had to pay a woman thousands of dollars to stare at me and just to get me to not drink.”

But. he admits, “I didn’t learn s—.”

Grande said that after the coach was done, he decided he was allowed one drink a month. Then he upped his allowance to two drinks a month. “And then it was one drink a week, and then it was one drink a night, and then it was every night again, and it was just wasted, wasted, wasted.”

As the “Boys” singer told Kent, “when I realized that I had gotten back into the swing of things so easily after paying that woman for ninety days, I was like, ‘Oh, s—. I think I have a problem.’ “

Grande decided to hire her a second time when he was invited to joinBig Brother. “I knew that if I went into that house and had to detox on live television, I would be a f—ing disaster,” he said. “I was smart enough to know, ‘You’re an addict, you’re an alcoholic, hire that bitch, detox for two weeks, go into the house.‘ ”

And he was still sober when he leftBig Brother— until the reality show’s afterparty.

“Something happened. Somebody said some s— about, I don’t know, tweet, about f—ing on Instagram, whatever the f— it was. And there was a drink, and somebody was like, ‘Do you want a sip?’ And I was like, ‘Yep.’ And then 43 seconds later, calling my dealer and back to the races. And harder than ever, because I had just gotten off that experience.”

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SInce then, Grande says, “I’ve learned to basically stay out of the comments.”

He shared that reality TV is “such a trigger. It’s a really tough environment to be in,” explaining that it’s “demanding on your psyche, on your body, and on your humanity, especially with someone who’s staying sober.”