Can you find a way to explain constipation to your DD? You could explain that it doesn't happen very often and that there are lots of foods, combined with drinking lots of water that soften the poo inside so that she can poo easier. Also explain that holding onto poo is bad for her body because all that left over that her body doesn't want needs to leave her body, or it can poison it (simple language that you can develop as she gets older to build on the concept).
Clever baby! And congratulations Enjoy all that ECing can teach you about your babies xx