Hi My Daughter Is 2 Years Old And I'm Separated

Hi my daughter is 2 years old and I'm separated from her mother and recently my daughter's doctor has said she may need a bit of speech therapy just to help her along but I have learned that her mother has been teaching her sign language instead of helping her speech my daughter's health is perfect as de doctor said to me but I forgot to ask would the sign language effect her learning to talk as a lot of people have said it is effecting her please can u help me as a worried father