Can my girlfriend's dad block my number?

My girlfriend just got her phone back recently, but hasn't been able to use it yet. Her dad controls the phone bill and the settings and service.

However, what I was wondering is this:

Can her dad block me from calling -- if so, can he also block me from texting her?

Another thing: if he blocks me from calling her number, can she still call and text me?

Thanks!

(By the way, she goes through Sprint and I go through Verizon, if that makes any difference.)

Only text messages ..not voice calls