Personally, I like to keep it to no more than two under 18 months and three under 2 in total. I find it is okay when they are babies, but once they all hit the toddler stage together, it is hard when they are all the same age. I also like to have no more than two non-walkers as it is hard on the back all the lifting and carrying. That said, I do have a 6 seater stroller as I did have three 12 month olds at one point and I decided I might as well have a stroller than can hold everyone so I am never stuck. Some people love having all babies, some people don't. It depends on you.