Cute observation

:).

Only because you’re saying that “Mary IS wishing…” which is present tense, so you want to keep the whole sentence in present tense. Otherwise, it’s fine! :] Good job with the THEIR. :]

haha My own sentence right there sounds pretty horrible. Sorry.

Mary wishes her smiley faces didn’t always have moles on their chins at the end of the sentence.”

The word “sentence” can be either singular or plural.

Make it:

Mary is wishing that her smiley faces didn’t always have to have moles on their chins at the end of her sentences! :).

Oh, and a tip to get around the mole thing, try putting two dots at the end of whatever you are saying, so it looks more natural, as if you weren’t done speaking:

Mary is wishing that her smiley faces didn’t always have to have moles on their chins at the end of the sentence! 🙂 …

although I’d rephrase it as “didn’t have moles on their …”, removing the “always have to”. But whatever it’s just a status message.