AITAH For Purchasing A Home With A Pool And “Triggering” My MIL?

37F here. I'm a mother to seven year old twins (boy and a girl) and a five year old girl. My husband and I decided to move back to our hometown so we could be closer to both of our families. Our hometown is a lazy, beach town and I've been living cities since college. It's not my ideal location, if I'm being honest, but I am excited about being outdoors and in the water more. My husband and I made a "deal" that since I agreed to move and find a new job, we'd get a house with a pool, which is something I've wanted since I was a kid. It's not actually that serious, but it's something I've been excited about since we decided to move. My husband and I found the perfect house, and we're currently in escrow. The house is walking distance from the beach and my parents, each of my kids get their own room, and there's a pool (with a water slide). We're all so excited.

Some important context is that my husband was actually the oldest of four kids, and the only girl in the family (who was also the baby) passed away when she was eleven. She was swimming with her friends in a lake, got caught in some shrubbery, and drowned. It was tragic for the entire family, and I don't get the sense that my MIL has ever recovered. My husband's home is filled with pictures of his little sister, the kid's bedroom is basically a shrine to her, and my MIL gets teary anytime she sees one of my two daughters. My MIL has always been kind to me, and is a wonderful grandmother, and so it's difficult seeing her so sad.

Yesterday, my husband and I were on the facetiming with his parents, and I sent them pictures of the house we're moving into. My MIL's face went white and she asked how we could possibly move into a house with a pool with three young children. I explained that my kids are all great swimmers, that we've told them there's absolutely no swimming without one of us there, and that we're getting a gate with a lock and alarm installed around the pool so they can't get into it without us. My MIL started crying, and saying that drowning is the leading cause of death for young people. She also said she couldn't believe we'd be so reckless with the lives of our three beautiful children. My husband tried to calm her down, but she was furious, and hung up the phone.

My husband now feels terrible, and says we should have thought more about moving into a house with a pool. He's not worried about something happening to our kids, because we're going to take the proper precautions, he's worried about his mom's mental health. He says his parents will never be able to come over now, because his mom will be watching the kids and the pool obsessively. He also says we're probably not going to be able to do holidays or parties at our house because his mom will be even more anxious with all her young grandkids near the pool. I've seen her anxiety around kids in the water first hand. Once, we were a a family reunion and there was a lazy river at the hotel, and my four year old nephew who couldn't swim was wearing a life vest and flipped over for about two seconds. My MIL jumped in (she was wearing a dress and heals) and grabbed him right away.

Please tell me if I'm a total asshole, but I don't think we were wrong to purchase a house with a pool? My MIL has serious trauma (which I understand), but if we listened to all of her worries, our kids wouldn't be able to do anything. For example, our son wants to take surfing lessons, and my MIL is against this because she thinks so much time in the ocean is dangerous. We also put our youngest daughter in swim lessons very early (a bit over a year old) because we want her to be safe and comfortable in the water. My MIL said this was way too young and dangerous, and I said it was a great teacher and I was in the water during the lessons, but my MIL was still furious.

All of this to say, maybe we were a bit insensitive moving into a house with a pool, but she's triggered by so much of what we do. AITAH? Any advice would be appreciated.