Re: solids causing constipation?
How many days has it been? Up to a week is normal for an exclusively breastfed baby, but I'd say a week is probably still normal for a baby who has had just a few tastes of solids and is still almost 100% breastfed. That being said, you did choose 2 infamously constipating solids: apples and bananas. If you suspect your LO has a tendency towards constipation, I would take those off the menu until he's eating lots of solids and is in a 1x per day pooping pattern.
Remember that solids are supposed to be introduced starting around 6 months, and that quantities should be very small at first. A teaspoon or two per day is all a baby really needs to get, and since breastmilk alone meets all baby's nutritional needs until around the first birthday, it doesn't matter if baby eats his solids or not. Touching, tasting, smelling, squishing, smashing, even flinging- those are all important parts of the solids experience. Actual eating, not so much, at least until around a year.
Coolest thing my big girl said recently: "How can you tell the world is moving when you are standing on it?"
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