by 5 months with all 3;
#1 had a pacifier, slept independently and I went back to work full-time at 12 weeks
#2 was/is a thumb sucker, co-slept and I went back to work full-time at 8 weeks
#3 ebf on demand, co-sleeping, no pacifiers, no bottles until I went back to work part-time at 6 months yada, yada, yada

actual fertility returns between 11-15 months
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