Oh Lord! I have three boys, ages 5, 4, and 2. The first two are 14 months apart, the second are 18 months apart.
Unlike you, we didn't plan the third, he was a blessing! My mother had recently passed away and I lost track of birth control under the grief/stress.
I can tell you the pros and cons, and you can decide.
The pros:
The kids are so close in age, they love the same toys, shows, movies, games, going to places (museums, Chuck E Cheese, etc). If your kids are 12 and 11, and the other 5, they are not going to be into the same things.
All are in/out of diapers/car seats about the same time. Once you're done you're done.
My boys will all be in high school and college at the same time (well that's a pro for them to be close, but a con for $)!
Cons:
I sometimes see parents of one or two children, and think, "man, they have NO IDEA how much easier that is!" than having 3.
You don't get much one-on-one time with ANY of them. If you take one somewhere, your husband with have two. I really really miss that the most, the one on one time with each child. We all usually go somewhere together.
Eating -- I have them all raise their hands to speak at the table, otherwise it's madness.
Noise -- 3 become a sort of "pack" and run alittle wild and become deaf to the sound of your voice!
Overall Abigail, it comes down to multitasking and having to do everything at once, depends on what type of person you are. Easy going, stressed, etc. Knowing what I know now, we would not have had a 3rd so close in age. Right now -- my 5 and 4 year olds would be great with a baby -- but I have a 2-1/2 year old instead and I often feel like they are each missing out on time with Mommy. And my husband of course doesn't get as much attention either.
However, like I told you, my 3rd was a "suprise blessing" not a choice -- and he by far is the best baby (easiest) and he just melts my heart and I adore him. I often feel ilke he was a gift from my late mother... I wouldn't have him if she hadn't passed away.
Consider why you want a 3rd child? For you, for your kids? Or do you just want a large family?
If you do have another, God bless you, and you can do it, and I pray all is well (and peaceful) at your house!! If you wait, I know your kids will help you with the baby and maybe you'll then have a 3rd and 4th (so they are close in age).
Email me any time. ==V.