It sounds as if you have tried all the right things and if they are not working, you may be dealing with a more chronic constipation issue. MN is right it is time for further action and there are treatment options which are gentle and will not lead to dependancy. Your gp or pharmacist should be able to help you out, rest assured this is easily treated when you have the right advice I went through similar with my dd and it turns out to be quite common. Distressing, yes, but common.

Unfortunately it took me a few gps to get answers as not all are great with knowledge about the difference between toddlers and adult type constipation. Great that you are getting on to this early as MN is correct that it can lead to a lot more distress if not sorted out.