Gender and number agreement with past participle

Question

I am reading this French article on nautiljon to improve my French. This is about a Chinese couple that lost their child only to be reunited years later.

Wang Mingqing et son épouse Liu Chengying ont perdu leur fille, Qifeng, lorsqu'elle avait 3 ans. Le couple chinois qui n'a jamais perdu l'espoir de retrouver son enfant un jour, l'a revue ce mardi, vingt-quatre ans après sa disparition inexpliquée, rapporte The Independent.

In the second sentence there is a direct object pronoun "l'" in "l'a revue" referring to the child. But I noted that they use revuE, so they made the past participle female, because it it is a little girl I assume.

I know there is an agreement in gender and number with the past participle for direct object pronouns that precede the verb, but how do you decide if it is female or male here. Because you could argue that it should be "l'a revu" too no? ... because un enfant is 'male'?

On what basis do you decide if the past participle should agree with "une fille" or "un enfant"?

Answer 1

Enfant is one of these few words called épicenes, i.e. which has the same form for both genders, is masculine and feminine.

Here we know the child is a little girl so she is une enfant.

What might be even more confusing is despite being used in its feminine form, the masculine possessive son is used but this is for euphonious reasons.

The fact is sa enfant is impossible, like sa amie becomes son amie.