My 5 year old son has been on Leucovorin about 11 days. It's improved some behaviors. He will be still and let me cut his hair (even smile about it), he lets me cut his finger/toenails. Previously he would cry, yell, scream, hit until I stopped. He will now wear his backpack, he will take pills, drink almond milk.Those are things he wouldn't do at all before. He is saying more vowels and making more sounds, no words. Just going to keep thinking positive and see what happens next.