have vs having

[Batal]

What is the difference in the meaning of the following sentences?

- You smile a lot when you have a baby.

- You don't smile much when you're having a baby.

[Joe]

Your confusion is caused by the two different meanings of "have" in this context:

1. to have [something] (verb): to own, to possess
2. to have [a baby] (verb): to give birth, to deliver a baby

- You smile a lot when you have a baby.
This is sense 1, a state, used in Present Simple tense.

- You don't smile much when you're having a baby.
This is sense 2, an action, used in Present Continuous tense