Trip to UK

[RichardHussey]

Hello,
I am a British citizen who has been living and working in Spain since August 2016. I have my NIE/residency. My wife and stepson from the Dominican Republic joined me in November. They both have their 5 year residency cards which state that they are family members of an EU citizen ( Familiar ciudadano de la union) and under observations it states resident (residente).
My father has invited us over to the UK for a holiday so my wife and son can get to see the UK.
My questions are:
Does my wife need a visa?
Do we have to pay for one?
Where do I apply for one if needed?
Thanking you for your help and advice in advance.
Rick

[secret.simon]

As your family members have Article 10 Residence Cards (family members of an EU citizen ( Familiar ciudadano de la union)), they can travel anywhere in the EEA without a visa, provided they are travelling with you or travelling to join you in another EEA state.