Pool and water safety is extremely important. I ask parents to really focus and hear me out here because the accidents happen so quickly, and they happen silently.
First off, I would make sure or implore with parents who have a pool or a spa, to have it covered. Make sure that they have a current, up to regulation, cover; whether it's a fencing or an actual cover. It's up to you. You pick which one works best, and implement that and use that. Then I would also recommend a second layer of protection; which is making sure that any perimeter door in your home, that could lead to that outside body of water, is locked. Perimeter doors and covers are paramount for pools and spas.
When you have a baby, it's important to make sure that you have what's called "touch supervision," when you are in the water with your child. Don't trust the little floaties that go on their arms or any other little floating device, with you in the lounge chair and them in the pool. That does not work out and is not recommended. Make sure that you are always right there and focused on your little one.
In addition to the pool, make sure that when your child is in the bathtub, that you have touch supervision there as well, and that you never leave your child unattended in any body of water.
One thing you may not have considered, after a rain you need to walk out into the yard, survey the area and make sure that, perhaps a pot or one of your children's toys or a water table, hasn't collected any of the rainwater and become a potential drowning hazard for your child later when you send them out in the yard to play. Make sure that you topple those, so that your child can play safely in your yard.