Grandpa will wait for you until you finish eating breakfast, so you don't have to cry.
No need to cry, you can hang the laundry outside with grandpa after breakfast. He'll wait for you.
ーGrandpa will wait for you until you finish eating breakfast, so you don't have to cry.
「おじいちゃん、あなたが朝ごはん食べ終わるまで待っててくれるから、泣かないの。」
wait for someone で「誰かを待つ」
finish eating breakfast で「朝食を食べ終わる」
cry 「泣く」
ーNo need to cry, you can hang the laundry outside with grandpa after breakfast. He'll wait for you.
「泣く必要ないよ。朝ごはんの後おじいちゃんと外で洗濯物干せるから。(おじいちゃん)待っててくれるから。」
hang the laundry outside で「外に洗濯物を干す」
ご参考まで!