If you would consider a bit further afield, Inishcoo Island is magical. See
www.inishcoo.com. You can fly via Dublin to Donegal airport which is only about 15 mins drive from the port. Then it is just a short boat ride to the island. The island is 100 acres of heaven! Inishcoo house has just been restored and has six double bedrooms and a single room and a cot room, as well as a dormitory which sleeps 8 children. It has beaches galore and although there are 2 other cottages on the island, they are very rarely used so you usually have the island to yourself. The rental includes a few trips with the boatman, and he can be paid directly for extra outings. The place is all about fishing, lobstering, beaches, walks, and good old fashioned fun. It is well set up for children with highchairs, assorted small wellies, cots, washing machine, etc and is safely fenced from the sea. I confess a close connection with it, but I know that everyone that goes there falls in love with it.