Hi all mom's ..my kid has completed his fourth month...but for the last one month he is not urinating much at nights ...many days not even one time...he sleeps through the night...once he gets up, he passes hard urine for the frist time ..and then it is normal...his urine count is also normal... he is sleeping by 12 or 1 clock at night and used to wake up by 9or 10 am in morng ...i am very worried as he is not at all urinating all through this time  and might it cause any trouble in future...What should i do ?