It could be argued that Amazon is like a fairy godmother for moms everywhere. Need some ballet slippers? Amazon will deliver them in two days. Did the stomach flu hit the whole family? Amazon Prime Now will have Saltines and Gatorade at your doorstep in no time.

Now, Amazon is making even more dreams come true by offering free grocery delivery to Prime members. Amazon Fresh, the delivery service, is only available in select cities (for now, but it's expanding) and previously charged customers a $14.99 monthly fee for the grocery delivery - on top of the annual Prime membership fee.

After purchasing Whole Foods two years ago, Amazon began offering free two-hour Whole Foods deliveries to Prime members through Prime Now, but Amazon Fresh, which is only available in 20 cities as of now, has more food options including produce, meat, and dairy and don't necessarily come from Whole Foods.

Here's the only catch (for now), since they're just starting to expand the program and roll this out, only customers who have previously used the Amazon Fresh service have access to the now-free benefit. Not to worry, though. Any Prime member who wants to sign up for the service can ask for an "invite" (or, in non-marketing terms: add themselves to a waitlist) to have access to the benefit as it continues to roll out.

Grocery delivery isn't new. Moms everywhere have been using services like Instacart, Shipt, and WalMart for a while now because no one enjoys dragging screaming kiddos through the store when they just need to pick up some milk and chicken. Still, Amazon adding this service - for free - will make them reign superior in every facet of parenting convenience.

If this venture is profitable for Amazon (which it probably will be), it has the potential to make a huge difference for families. Without delivery fees, grocery delivery opens a large chunk of time that parents can instead spend with their kids (or by themselves, whatever works) and save money in the process.

At this rate, it won't be long before Amazon takes over the world.

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