If you know you’re someday going to have more than one kid, I’ll be straightforward, make a larger age gap between them. Save yourself. A few years won’t make a big difference for them, but it will for you.
Let me tell you, from experience. Kids, when they are very young (I’m talking bellow 3-4 years) don’t know there is two (or more) of them, and only one of you. That’s why you will be torn between them. They want their needs satisfied and don’t really care about others. So, for the first couple of years you are going to be only a service, mom service.
Not only will it do good to you, but to your children as well. The fact is that when you have two babies, or toddlers, or a combination of both, it’s hard to give them the amount of attention that they want or need.
So make your kids AND yourself a favor and wait 2-3-4 years till you get pregnant again.