Can lifeproof iPhone case survive punches?

My sister had her iPhone with her lifeproof case on it laying on her bed and she got mad at her boyfriend punched her phone while it was laying on the bed like 3 times. Is her phone okay? Will it cause problems in the future?

I doubt your sister's fist can penetrate gorilla glass and plastic.

Don't worry about it. If it's still working fine then you shouldn't have any problems. I would however recommend that your sister invest in a punching bag.