"The child asks: "Where is mum?""
Translation:La infano demandas: "Kie estas panjo?"
According to Wiktionary, infanino is perfectly valid.
I had heard that the affix ge- couldn't be used like this; it's defined as meaning "of both genders". However, there has been some discussion in other threads that it could be used as a gender-neutral term for a person of unspecified (or ambiguous) gender, but it's not an official part of the language that way as of yet.
'xx said: "something"' is correct English. It was in fact the preferred style of E. Nesbit, a famous novelist. See, for example:
"The Railway Children" http://www.gutenberg.org/files/1874/1874-h/1874-h.htm
Could you name some style guide(s) as well? In any case, I understand that the guideline is to use a comma for quotes as short as these: http://www.grammar-monster.com/lessons/quotation_(speech)_marks_colon_or_comma.htm
We can use the style guide that you cited. Here's what it says, after having suggested the comma for short quotes:
"Nowadays, it is acceptable to introduce a quotation with a comma, a colon or nothing. In modern writing, the choice of punctuation depends largely on the desired flow of the text (i.e., how much the writer wants the reader to pause)."