When I started my direct-selling business, my children were two and five years old. They had never had a babysitter, so I definitely was "Motherhood-Smotherhood." It was pretty traumatic for everyone when I began my business and started leaving the children with a babysitter. I realized right away that / had to get them to see the benefits of my working and what was in it for them.

--- I'm not sure how to understand "what was in it for them"?

It's kind of hard to explain but let me give you an example

Q; Do you like soccer?

A; No, there's nothing in it for me. (= there is nothing in the game of soccer that I like or will benefit from)

Q; What, you're a member of a pop band now. But you hate pop music.

A; I still do, I'm only in it for the money. (=the only reason I've joined the band is because of the money)

Going back to your original sentence, the 'what was in it for them' part refers to the mom's business/working and how will that affect her children
Students: We have free audio pronunciation exercises.

So, she's saying that her children should know what this job can give them.
Basically yes, including both the pros and cons that go along with it.
Thanks for the answers.
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