Eleven-month-old Zakari William Bennett-Eko was rescued by firefighters from the River Irwell in Radcliffe, Greater Manchester, on Wednesday afternoon but died in hospital shortly after.
His father Zak Eko, 22, has been charged with murder following the baby’s death.
The child’s mother, Emma Blood, said it was “hard to comprehend” what had happened after being told Zakari had died when she arrived at the hospital.
She said: “On Wednesday afternoon my life changed forever.
“I woke up that morning being a mummy to the most wonderful cute little boy and by the afternoon Zakari was taken from me in the most tragic of circumstances.
“Zakari was my life for 11 months and will be the heart of our family for many years to come.”
She described Zakari as a “happy and content baby with a gorgeous little smile and a head full of curls” who made everyone he met “fall in love with him instantly”.
Ms Blood added she found it hard to imagine that “I will not get to see my baby grow up to be the handsome decent man I knew he would become”.
Tributes to the little boy have been left at the bridge near to where Zakari was rescued.
One card read: “To a beautiful little boy. Sleep tight little man. Our thoughts are with your family.”
Another read: “Goodnight and God Bless beautiful innocent boy. Fly high Angel.”
Greater Manchester Police has urged anyone with information to come forward, adding that there was “a significant number of witnesses to what happened”.
Zak Eko, of no fixed address, appeared at Manchester Magistrates’ Court on Friday.
He was remanded in custody and will next appear at Manchester Crown Court on 16 September.