My 8 year old daughter has been taking Singulair for 4 years. She...

My 8 year old daughter has been taking Singulair for 4 years. She immediately began having sleeping problems. I never connected it to Singulair. When she was 5, she had a check-up with her Asthma/Allergy doctor. I received a new prescription and had it filled at Costco. She became more irritable and the sleeping problems persisted. After I had the second refill and had the information sheet Costco had given me, I decided to read the about side effects. That was when I realized she was taking the 10mg dose for ages 15 and up at 5 years old. I knew she was taking a different dose but it was new script because she had been at the doctors and I thought the doctor had just increased the dosage. I called Costco and had them check the original prescription and sure enough they had entered it wrong in their system and was given an OVERDOSE. They did pay for any tests for Physical damage (blood work and liver), and gave me free pills that were dispensed incorrectly. I assumed everything was ok now that she was back on the 5mg. dose again. She has still continued to have sleeping issues and her aggressive behavior has gotten worse. She has consistently had stomach problems, daily! A month ago I had an evaluation done for academic purposes, When the Psychologist was done he was saying she was a sweet girl. I proceeded to tell him about her violent outbursts. Just that morning her brother, 6yrs.old, was walking by her and out of the blue she took the pencil in her hand and slashed across his chest. I told him these were typical of the behavior at home and I had tried all type of discipline to no avail. HE WAS SHOCKED. He said that wasn't her personality at all. After talking to him a second time, He said it was probably a combination of her age, hormones starting to kick in and sibling rivalry! I knew it was more than that but still never connected it to Singulair! Well, as of today she is off the Singulair. I can't wait to see if her behavior changes. I see these posting go all the way back to 2003! If only I had thought to look online first!