//all of the code below are in the same ino file.
class Animal{
public:
  bool alive = false;
  Animal (bool liveStatus){
    alive = liveStatus;
  }
}

Animal dog(false);


void setup(){
  dog.alive = true;
  //here when I print dog's alive flag it's true
}

void loop(){
  // here the alive flag of dog is still false  , it should be true!!
}