13 months old? One, your kid is one.
You must not have a child lol.
You tend to label them by months for a good while simply because of how fast they are learning and picking things up. We record all of his first, and there are a lot of them. The difference between a 12 and a 13 month old is much larger than a person celebrating their 18th birthday and that same person a month later.
I was the same way, by the way, before I was a parent. A lot of things I never understood until I had my own child. You are free to continue calling him a one year old though. I have no problem with that.

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+ 1 billion Internet posts for pointing out he is one year old. It's a pet peeve of mine when people refer to a babies or toddlers age in months once they hit 1 year old. It's pointless. Also, why the heck would you let a 1 year old play with a brand new and expensive iphone 6? No way would I do that.
I answered why I label him as 13 months. Years, months, weeks, etc are just arbitrary ways of measuring time. As I said, time moves a little faster for wee ones. The fact that it bothers people to this extent is astounding. Also, and this may shock you, medical records are all in weeks and months. You tend to go to the doctor a LOT before they hit two (I tried really hard just for you to not say 24 months).
Anyway, it's just a phone. In a case. With a screen protector. On carpet. He can't do any damage. And if he could, insurance.
One thing I have learned reading through threads though, is that if you ever mention kids, you always get awesome parenting advice from people who probably don't have kids. And even if they do, you never asked for it in the first place.

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Looks like your wife enabled erase data when she entered her fingerprint and forgot about it. I don't have this enabled as I have kids for this reason.
This is what the answer was. I wa surprised because she never did this before. New phone and, well, guess she just clicked "yes" to everything during setup lol.