Thank you for your query,
Your child is having loose motions since birth means almost 13 months is quite unusual.
What is her present weight?
Is there any weight loss?
It is chronic diarrhea
syndromes, intolerance to lactose, fructose and sucrose to be ruled out by stool examination.
Some times chronic nonspecific diarrhea will present in toddlers with chronic diarrhea.
Your child needs evaluation, trials of lactose free diets, restriction of oral intake of fluids if it is more than 150ml/kg/day.
So be in regular follow up with your Pediatrician
and gastroenterologist for the full evaluation and management.
Hope I have answered your query.