Re: What happens where they turn one?
Nothing magically happens when they turn one. I think lots of people use the 1 year mark because by that point usually baby's digestive system is developed enough to be able to handle things like eggs and cow's milk (though they can still be allergic to those things).
I've not ever actually heard anyone say you should wait until 1 year to give table foods. Lots of people never give purees, they just go straight to table foods. It's an approach called baby-led solids or sometimes baby-led weaning. There are a few good threads on here about how to do it or hopefully someone will come along and give you a good link.
We switched to baby-led solids after a few weeks of purees, so Nora was on only breastmilk and table foods from about 6.5 mos on. I stopped doing the 4 day rule about the same time, but there is no history of allergies in our family at all so I wasn't really concerned about it too much. I just watched closely for a reaction when I introduced something new, especially common allergens. If allergies is something you are concerned about, keep doing it the 4 day thing as long as you feel it is safer.
I would say that at 10 months your baby would probably do just fine with table and finger foods. Have you tried cheerios or bananas or anything like that?
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