[READINABLUESTATE]

...”Was more than one child attacked?”

Singular “they”
“They” and its inflected forms, “them”, “their”, “theirs”, and “themselves”, are gender-neutral third-person pronouns. They are often used when referring to a person who does not identify with a gender-specific pronoun. For example, when referring to “a reader” in a paper, one is not specifically referring to a woman, man, or someone of another gender.

[Blennos]

To my ear, if the sex of the child is unknown, it would be better to say “the otter dragged it underwater.” “Them” seems bizarre to my language sense.

[Petrosius]

Singular “they”
“They” and its inflected forms, “them”, “their”, “theirs”, and “themselves”, are gender-neutral third-person pronouns.

BS! "They" is a plural pronoun. The reporter should have done her job and inquired of the sex of the child, and used the proper pronoun. In cases of when referring to a generic person then the proper use is the generic use of "he."