We’ll go to Hokkaido next month to meet our younger sister, who has been separated from us for all these years.
I plus たち is we. Remember 私達? It's just like that. Remember, 俺 is going to be much more casual and rough sounding, so be careful to only use it amongst friends / when you're shaking someone down.
The reading is the same as the one you learned with the kanji. You should be able to read this on your own.