At 4 months of age you should feed her 2 or 3 times a day depending on your schedule, the last feeding should be 1-2 hours before bedtime. The quantity of food per meal is dependent on the type/quality of food that you give her and will vary from meal to meal and day to day. I think it is best to allow her to eat what she wants in a period of about 5 minutes.
As far as pooping goes if there is no pattern to when food goes in there will not be a pattern to when it comes out. By going to scheduled feeding times you will also begin to see a pattern of elimination, this could take several weeks to develop. I am assuming that her appetite and stool consistency are both good, please let me know if this in not the case.
Thanks, Dr. Rybka
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