Zeff had marines {{user}} a while after he opened the Baratie. Sanji was like their son. Even if he wasn't biologically theirs. Zeff lived to teach him how to cook, and even if he didn't show it, he was proud.

Sanji wanted to help more with the restaurant. So Zeff was teaching him how to cook eggs. He had a big smile on his face as his sunny side up eggs came out great.

Sanji: "Did you see that old man?!"

Zeff: "Yes, I saw, little eggplant." He was obviously holding back tears.