The biggest-selling drink in Moose Jaw this weekend?  Lemonade from Cassidy's Lemonade stand. 

Moose Jaw's Cassidy Evans suffers from Cystic Fibrosis, and is continuing her quest to fight the disease by quenching the thirst of hundreds. 

Cystic Fibrosis is a genetic disorder mostly affecting the lungs, making it difficult to breathe, causing lung infections, and can also affect other internal organs.

9-year old Cassidy was diagnosed with the disease when she was four, and needs to go for checkups every three months. 

Cassidy's dad Jesse shows off specially-made t-shirts for the event

"It's a bit of an 'invisible' disease," said Kimberly Evans, Cassidy's mom. "You don't always see the symptoms from the outside. She's had a few hiccups this year and has had some bad bugs we've had to take care of but she's healty, active and doing the best she can to find a cure for CF."

As for the lemonade stand, the Evans' are continuing a tradition that started when they lived in Saskatoon - shortly after Cassidy received her diagnosis. They operate a lemonade stand with all proceeds going to help fight CF. 

"The first two years (of the lemonade stand) were in Saskatoon, then 2014 we moved here and 2015 was the first year in Moose Jaw," said Kimberly, who said they expect to sell around 1500 glasses of fresh-squeezed lemonade between Friday and Saturday (June 23 and 24).

"To date we've raised over $20,000 at the lemonade stand for Cystic Fibrosis Canada."'

The lemonade stand is open Saturday from 10 a.m. until 3 p.m. and there will be bouncy castles and other entertainment on site at their home at 1121 Simpson Avenue.

Lemonade will be sold at 1121 Simpson Avenue from 10am-3pm Saturday