Mine don't have blueberries, the only time they have ever puked it was after eating blueberries, both of them, both times

Shame because I love making stuff with them.
Raisins I used to halve until they were about 14 months, part of that was because here they are massive and if you halve them they don't inflate in their poo and I always found that really weird.
I still quarter grapes and break olives a bit, only because they shove them in their mouths so quickly and I think it's habit now.
I read somewhere that grapes & cherry tomatos should be halved for ages, I can't remember how long but I was surprised.