to wonder what to do about what I saw with friend's au pair

[phewIdidit]

I was at the park the other day with my son. We were there a couple of hours. A friend's children were there with their au pair. Initially I thought their mum might have been with them but they told me they were with the au pair. I asked them were she was. The older of the two pointed to a woman seemingly asleep some way off from the park in the grass - not facing the playground. The children she minds are 9 and 4. I was a bit taken aback. She remained in the same position for the entire time I was there. At one stage the younger child had a minor mishap and the elder child took the younger one to the au pair.
I realise being an au pair is low paid and the job description is a bit vague.
I don't particularly want to be a busy body however I wouldn't want my child to be fairly unsupervised in the playground. What do others think is the best course of action?

I don't think a 4 year old with an older sibling is far too young for the adult to be on the grass outside the play area. I do this with my own 4 year old and they have no older sibling.

If the OP thought the situation was actually dangerous they'd have done something at the time, but obviously they didn't.

Tell the mum. It's up to her if it's a big deal.

Nobody has actually said that the dc aren't capable of playing by themselves FFS.

Those posters spouting about how lax their parenting, suggesting the rest of us are loons, clearly wouldn't mind if something happened to their dc whilst in the this persons care [sceptical]

This person was not the parent but a person being paid to look after the dc, so the least their parent would expect is for that person to be aware of where they were, not laying down seemingly asleep.

Aside from that the 9 year old shouldn't be responsible for his 4 year old sister.