What do you tell a 3 year old?

Had a growth scan yesterday... baby is still growing at her own rate. She is measuring almost 2 weeks small but is following her own curve.  She now weighs around 2lb 1oz. Dr did say we will deliver between 34-37 weeks, but is hopeful we will make it to 37 weeks.
I met with Dr Growney today for my regular appointment. That went well. Uterus is measuring same a baby 26 weeks, I'm 28 right now. I've already gained 11lbs since the start of pregnancy. I feel great, but starting to get tired again.  Baby moves all the time. From here on out I will be busy with appointmets. Every Tuesday I go to Springs for a Doppler with high risk Dr. And starting next Thursday I will go to my Dr for BPP scans (watches babies breathing, movement, fluid levels, ect) along with an NST (watches heartbeat for 20 min) followed with a quick visit from the Dr.

Lately Averi has been talking about "a baby in mommies tummy coming soon".usually we just ignore her. We haven't told the girls anything so not sure where this came from. She is very smart for her age. So we told her tonight that mommy has a baby in her tummy that is a special present for our special friends Q&A. We continued to tell her that not all mommies tummies work and some are broken.  So her mommy (Me) has a baby in her tummy to give to Q&A since A' s tummy is broken. Not sure how much she grasped and understood. We don't plan on talking about it unless they ask more.