My father s my daughter?

I have a two year old daughter Alana who acts like a normal two year old, she likes to run around, throw her toys (in a fun manor), and just act cute. My father started her because she threw a block at the refrigerator. For the record I grew up being ed by him with belts, wooden spoons, etc and I swore NEVER hit my kids and I never have yet. Now he started hitting her and says it's the only way she will learn. I don't know what to do. My daughter loves him but I don't want her to be ed, especially because she's there every morning while I'm at work. I'm scared to leave her there, and my dad won't listen to me when I say to just tell her what she's doing is wrong. Please help, I don't want to stop taking her there cause my mom loves having her there, and I don't want to upset my mom. Should I let him her? I'm really confused what to do. Sorry if there is spelling errors, I'm on my phone.