Just a question.

Can you say:

She is going to be two in two days'time (or in two days)
I'm going to Sicily in a month's time.
Is "time" optional?

Thank you

You can say these things either way, but if you drop "time" you also drop the apostrophe.

She will be two in two days.
She will be two in two days' time.

I'm going to Sicily in a month.
I'm going to Sicily in a month's time.