I think NO ,because she cannot see because of some problem and I have read that it was very difficult for her learn and study things .She was also sometimes upset because of this .She had also faced many troubles but she never give up. So that's why I don't think she had a happy and easy childhood.
But she was very happy when she achieve her goals of her life and became so famous that everyone in this whole world knows her name.
Have you ever come across a saying a smooth sea can never produce a skillful navigator yes  keller was an active sea who produced a skillfull navigation in the lives of many differently abled people i think she had a happy childhood because she never felt bad for being a disabled person she was a  person who saw the world with optimistic lenses as she alwalys enjoyed each and every moment during her learning with her teacher anne so according to my point of view she had a happy childhood