Direct to indirect speech.

Question

I have a doubt if the following direct to indirect speech.  Which one of a & b is right? Thanks in advance.  Une mère demande a son fils

Answer

I'm not sure that I'm seeing your whole post. It seems to end at "Une mère demande à son fils".

That is correct, btw.

Une mère demande À son fils DE faire qqc.

I think the confusion comes when in certain instances you don't add either preposition after the noun.

eg) I would like to order a coffee. Je voudrais demander un café.

You wouldn't say Je voudrais demander au café... that's saying that you're asking the coffee to do something.

Hope this clears it up!