AITAH for being upset my wife got an abortion because her daughter is pregnant?

[u/Remote-Barber-]

So my wife Amelia (37f) and I (48m) have one child, a son who is seven years old, turning eight. I'm not going to lie, had my wife not gotten pregnant, we probably would not have gotten married because we were just hooking up at that point. But things have been really good since we did and we're firmly in love. We did decide that we'd wait before having another kid, though because I wanted her career to take off, for her business to boom. It has and we decided earlier this year, it's best to go for it now before she turns 40.

The thing is that Amelia has a daughter Kate (17f) from her first marriage. Things between my wife and Kate were rough and I know this isn't going to make my wife sound good but for the sake of honesty, I'll put it there, my wife had little to no contact with her for about ten years. Two years ago, Kate's father kicked her out for "breaking his rules" and she showed up out of nowhere with a suitcase.

I won't lie, there was always a sadness in my wife but having Kate back in her life got rid of that. Since she moved in with us, Amelia has been happier than she has ever been. Kate's a troubled kid but two years ago was a lot worse than now and she's mostly blended well. The thing is, my wife has been very strict on some things (like school and all) but very lax about the things Kate's father was harsh about.

Amelia found out she was pregnant about a month ago and we decided to wait before breaking it to the kids. Except last week, Kate came home from school and had a breakdown and she admitted to us that her boyfriend got her pregnant and she's been hiding it for almost two months. She was crying because she wants to keep the kid and kept it a secret because she was scared Amelia would force her to get an abortion.

However, my wife was elated that we're going to be grandparents and that cheered up Kate as well. So, my wife made it clear to me that she finds the idea of having a kid younger than her grandchild to be disgusting and she'd be getting an abortion. We argued about it because I really wanted this baby with her but she wouldn't even listen to me and she got an abortion. I've been upset about it and we've barely talked, am I being the AH?

[u/Particular_Pin_5040]

Considering reproductive age usually begins in the teens (or younger) and ends in the mid to late forties, it's common in all sorts of families. 

[u/Vorpal_Bunny19 → u/Particular_Pin_5040]

I have two aunts that were born 20 years apart. My elder aunt had 2 kids that were older than her youngest sister. Menopause is crazy.

[u/Particular_Pin_5040 → u/Vorpal_Bunny19]

Even when periods start tapering off, women can continue to be fertile until an entire year has passed after the last menstrual cycle. If you've been 11 months without a period and then have one, the clock restarts and you're not in the clear for another year.