Singulair and newborn baby

Update: Our son has been off of singulair since the 28th of March.....he had experienced most of complaints and ailments that affect other children. Since then, he is still tough to get to sleep - probably a 3 year old thing - but is better that before. He is also sleeping much more soundly and waking on the right side of the bed. He is still complaining of the leg cramps and sometimes still limping around for a while, and also complaining of stomach aches... I suspect those too should disappear after some time, however, he is no longer complaining that the lights and sun hurt his eyes. It is as though a major fog has been lifted - he is listening to us more the first time we speak rather than having to fight over things such as cleaning, or behaving. He is not as physical with us or his brother as before. And, the most important thing....he seems truly HAPPY - he has been napping all week at day care, and is proud of his accomplishment! He is focused in Karate class - listens to his Sir - engages in the activity with the other children - is more vocal and energetic....and once again PROUD! His Karate teacher - Sir - noticed an immediate difference in our beloved son - he was so surprised that Singulair is to blame - he said that our son is a complete different child without a trace of the drugged, insecure, and quiet boy he knew a week ago.
This Saturday our little boy will be testing for his yellow belt and he is so excited that he can hardly contain his HAPPINESS!!!!!

One last thought though.....I am extremely worried of any lasting mental or physical implications this drug could have on him - what does the future hold for our son - could this drugs nasty side effects cause some crazy long term side effect we have yet to see???