Dear parents,       You should know some facts for your concern. In 30mlboiled water one teaspoon ful milk powder should be added & in its multiple. In first 4months average wt gain is 750gms to 1000mg only if proper prepared milk is given. Now you wrote birth wt. 2.78kg&present wt. 4.79kg a gain of about 2kg   =0.750+0.750+0.5=2kg A good wt gain So cont same milk properly made.