Do german blue rams eat other german blue rams' fries? I mean not their own fries but the same species fries.
Sadly most ciclids will eat the fry of other ciclids if the fry is too small,most types of ciclids are agressively protecting their fry but the german blue rams might be too peaceful to do this.
If possible try to catch the fry when they start to swim freely in your tank to avoid them getting eaten,i know this can be hard to do as you need to quick before they get eaten.
You need to have a separate tank for the fry to grow until they get too large to get eaten,the fry tank needs to be setup in advance so it gets cycled properly before you add the fish.
Most aquarium fish will eat the offspring of other fish so if you want to take care of the fry you need to have a plan for how to separate them from the addult fish,this can be a floating fry tank or a separate tank.