Hi,
Great stories. More fun to learn than standard text books. Appreciate it.
A follow-up to "youle", I would lean towards the baby being born quite recently rather than 2 or 3 yrs old.  "youle" is more immediate.  The chinese says "wo youle", meaning I've got it. I got a baby. I'm pregnant.  If the sister is 2 or 3, I would think the family would be more adjusted to the idea.