I have daughter she will complete 4 years in october. She doesn't understand the instructions & does not speak anything & very much mischief. She switch on & off the light & exactly know the button she is very much expert to play youtube. If she want anything she catch our hand take us to there but never speak. She know a to z alphabets & 1 to 30 number & few animal vegetables fruits name & also recognize color very well. If she do any mischievous thing first look at us whether we are watching her or not if not then she do that. These are the few things she understand. But doesn't speak & follow instructions at all. Is it normal or what should I do. I don't have much time as she almost completed 4 years & unable to visit doctor in this corona pandemic. Please help.