Re: "Read to Child" not appearing.

No. It only works of the adult Sim has the "Childish" trait, oddly.

Seems weird that I can't do it when the book is placed in-world, or having a "Read something to child" option on the bookshelf.

Can you start a new game for testing purposes to see if you have the same issue

Need to test this.

I didn't have to, it started working on its own.

I think this is a bug, but if a sim has a sad moodlet (even if they aren't actually sad), the menu option doesn't appear.

I've tested this and couldn't duplicate. Option showed up fine although my Sim had a sad moodlet.

Do you still have the issue if they are sad ?

Tagging @jesterhatjolteon to see my answer above.

Are you still seeing this issue with the sad moodlet ?

in some bookcase, dont work nothing to do with traits, you have to < open bookcase > select book to read < put on table > and then try to read to child. 

Hi @Valdesca

moving this to the general forum as I can't duplicate and there was no follow up on this.

Do you still have this issue ?