Lagu died last night, aged 41.
Fellow artist and President of the Uganda National Musicians Association (UNMF) confirmed the sad news on social media on Monday morning.
“We took these pictures last Tuesday at the Jam Session and I can't believe you are gone dear Evelyn Lagu” Kenzo posted Monday morning.
“You have fought a big battle my sister and may your soul rest in eternal peace.”
Lagu has been battling kidney failure for over three years. She has been undergoing dialysis treatment twice a week.
The procedure involves mechanical removal of waste products and excess fluids from the bloodstream, that is usually done by kidneys.
Through her ailment, many Ugandan artists stood with the "Ogumanga" singer, occasionally extending financial and moral support to her.
Earlier this year, some of her friends put together resources and constructed a brand new house for her and children in Bujjuuko.
Lagu was born on June 1, 1982, in modern-day Kalungu district which was part of Masaka.
She grew up with her aunt in Mityana district following the death of her parents.
She went to Aga Khan, Mityana SS, and Pride SS Mityana for her O' Level education, and later St. Peter's Busubizi for her A' Level, which she finished in 1999.
Lagu started her music career as a back-up singer for some of the top artists including Carol Nakimera, Halima Namakula, Ragga Dee, and Mampi from Zambia. She has also played with the Mustard and Flash bands.
Some of her famed songs as a solo artist include among others Ogumanga, Ngukuwadde, Silkyatya, and Kasita Bakuleka.