Her baby will be allowed with her. The days aren't that long really, there's a lot of downtime throughout the day where Amanda will be able to stare at her baby.
I assume.
Presenters and actors often are able to have their babies close by/on set... its quite common.
12hrs sat on the sofa at home with a few breaks from visiting rellies, or 12hrs sat in a dressing room with a few breaks for the next take... there may well not be much difference.
But some people see the headline, and don't even try and assume anything other than how she must be a foolish/uncaring/matryr woman. Gets right on my nerves that does. She may be of course, but I always get annoyed when people think in the negative instantly, without considering that maybe she'd doing this after serious thought and is able to do it a way that wouldn't be open to the rest of us. [shrugs]
12hrs in a factory/office/ward is very different to 12hrs on set, in terms of continuous working. Its tiring, boring, time consuming la la la, but perfectly possible to be able to have a small baby around.