Mine are 21-28mo apart. We use NFP.
I try to space them around 2 yrs. (give or take a few months) If God wanted me to get pregnant sooner or later I would totally accept that and work with it, but I really prefer to wait until my baby is at least a year (despite the fact that AF has come back well before a year after most of them). When pregnant my milk supply decreases and I want to make sure they have as much milk as possible for the first year of their life (and nothing to interfere with that). None of them has ever had formula or a bottle period and I plan to keep it that way!
Another reason why I like them around 2 yrs is that it makes parenting them the way I do easier. I nurse on demand, child led weaning and so far they have weaned at 4.5, 4.8 and 5 yrs. Having them closer means I could end up nursing 3 or 4 at a time (I have nursed 3 for a year total) or my biggest fear is that it would cause them to wean before they were really ready (or that I would resent nursing because I am worn out from nursing so many for so long). I also nurse them down for bed and nap and I have been doing that for 2 kids for the past 7 yrs. We co-sleep too and so far each kid gets about 4 yrs of sleeping next to me which they also seem to appreciate (I only have 2 sides and after that they are full, so they can sleep on the other side of dh if they want

).
My hardest spacing was the one at 21mo. These were my first 2. I had a toddler who wanted to nurse and the baby who was high needs and dh who was out of town every week for 7mo. I often had to contort my body to nurse 2 down to sleep at the same time at night and for naps (which I would happily have to do if I had twins, LOL). With a spacing of even just a few months further apart, my older kid is usually better able to understand and wait to nurse (though there are still plenty of times I end up nursing 2 at once). Though I will say having older kids to entertain them till it is their turn for nap (or hold the baby for a few minutes while I nurse the toddler) makes it easier too, so maybe that closer spacing wouldn't be quite as hard now that I have older ones to help.
Oh, and I wear them a lot (we don't own a stroller) and though I can and have worn them when very pregnant and 2 at once, my body doesn't appreciate it too much
Anyway, I want to be able to parent and do the things for them that I feel is best, without having to compromise too much ya know. And so far for me 2 yrs lets me keep them close in age and still able to do what I think is best.
Kelley (forever long winded)
Sahm to Xian (9) Piper (7) Arah (5) Ever (2.5) and Thrace (5.26.09)
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