EEA citizens have the right to travel to Ireland and enter the country without a visa. Generally, as long as they can show a national id or passport confirming that they are citizens of an EU/EEA country, they will be allowed in.
There are, however, limited circumstances where EEA citizens can be denied entry into Ireland. That can happen when:
The EEA citizen trying to enter Ireland is carrying a severe contagious disease
The EEA citizen has previously committed serious crimes and is found to be posing a threat to public security.
If none of those applies to your circumstances, you do not have to worry and you will almost certainly be allowed to enter Ireland.