The baby aisle covers the products bought in volume and on short notice: nappies, infant formula, wipes and care products.
Nappies are chosen by weight rather than age, since the ranges deliberately overlap between sizes. Moving up a size as soon as night-time leaks appear works better than tightening the tabs.
Infant formula follows a strict age logic: stage 1 covers the first six months, stage 2 takes over at weaning. Value packs cut the cost per use, provided the shelf life after opening is respected.