YOU SAID:
pick me up at school at tomorrow morning with my sister and i please and thank you
INTO JAPANESE
明日の朝、姉と一緒に学校で迎えに来てくれてありがとう
BACK INTO ENGLISH
Thank you for coming to school with my sister tomorrow morning
INTO JAPANESE
明日の朝、私の姉と学校に来てくれてありがとう
BACK INTO ENGLISH
Thank you for coming to school with my sister tomorrow morning
That didn't even make that much sense in English.