FOREST HILLS, N.Y. – Two sisters from Long Island who have tried to lose excess weight their entire lives are crediting gastric sleeve surgery for their recent and continued success with weight loss.

While the operation is common, siblings being operated on by the same doctor on the same day is not and they shared their story ahead of National Sister’s Day on Sunday. Caitlyn and Cassidy Deerkoski have struggled with weight loss since childhood.

“A lot of my classmates and stuff, they’d always be like, ‘Oh well, you’re fat,”” older sister Caitlyn, 23, recalled. “’You’re a bigger girl.’”

Just two years apart, the pair has shared everything together— a room, the same friend group, and hardship trying to lose weight. They’ve tried countless diets and exercise routines and after much thought and consideration, they underwent gastric sleeve surgery in June.

Dr. Armando Castro, chief of surgery at Long Island Jewish Forest Hills, was their surgeon.

“All that we’re doing is removing about three-fourths of the stomach, reducing the capacity of the stomach to hold food and so instead of getting full after 10 to 12 ounces, our patients really fell that satiety, feel that sensation of fullness after four to six to eight ounces,” Dr. Castro explained.

The decision wasn’t met without criticism from friends and family.

“’Why are you doing that? Can’t you just work out?’” Cassidy remembers friends asking her. “[It] definitely didn’t make me feel good, but then I was just like, ‘I’m doing it for myself.’”

With a high body mass index and their weight in the high 200’s, they wanted to start feeling good and avoid health issues in the future that obesity is linked to.

The surgery was done robotically with Dr. Castro guiding a robot allowing for greater precision, less pain, and faster recovery. He knocks any notion that weight loss surgery is a quick and easy fix.

“I really would challenge someone to tell me that making a decision to undergo general anesthesia, a general surgical procedure, prepare for five, six, seven months, and have a recovery – that’s not terrible, but it certainly isn’t a walk in the park – tell me that that’s the easy way out for anything?” Dr. Castro asked.

It’s been a difficult road getting here, but the siblings lean on each other for motivation. They agreed they wouldn’t have been able to do it without each other. Their mother Dawn has been a pillar in the process too.

“I’m so proud of them and I love them and I know they always yell at me because they say, ‘You’re on me!’ or ‘You’re hounding me!’ but that’s what a mom does because she only wants what’s best for you,” Dawn said.

The sisters have a trip to Europe and a cruise in the Caribbean planned for next year and they say they’re looking forward to getting a whole new wardrobe for it.