When group lessons for music (as opposed to group music making) are mentioned, I often wonder how a child is supposed to learn very much, even if they have a good time mucking about. This article sums it up so well:http://www.simonfischeruk.com/English%2 ... laying.pdf
My inclination is for individual lessons.
If she is very young, being able physically to hold it will limit the duration of the lesson to say 30 minutes. Progress depends on so many things; quality of teacher, how much musical experience she has, amount of practice, let alone affinity for the violin. If she already plays another instrument and is familiar with the theory, then she only has to get used to getting the right sound from the violin. I have seen infant school children take between 3 months and 3 years to get to Grade 2 from the day they first held a fiddle in their hands. Then it can be a between one and three grades a year...
I hope she enjoys herself exploring it.