1. Studies undertaken as part of a lawsuit should be considered radioactive. See the whole Wakefield thing.
2. Infants don't drink the same amount of water as an adult.
Personal water intake history:
70's - 1993: Name brand bottled water from grocery stores
1993 - 1997: Self-service distilled or reverse osmosis water store, and remote pump at home
1997 - 2001: Carbon block, multi-stage, under sink filtration
2001 - 2018: Add reverse osmosis
2018 - present: Add UV stage
PSA1: Alkaline water is a scam
PSA2: Buy a water softener, whole house filter system, under-counter RO system, and maybe an indoor tankless water heater together on a wink-wink commercial purchase order (taxable) and have it freighted to your driveway (liftgate charge). It saves thousands on plumber markup and allows buying a TCO cheaper and better system.