The Parasites; by Daphne Du Maurier.

His bold daughter that was beautiful, her shy and sensitive son Niall who had talent in music, and then together the handsome, talented, elegant couple had a daughter Celia that was ordinary - even dumpy, always wondering why, what... and they were all within a year or two of age of each other.

The three children of the exquisite couple, brought up around theater everywhere, story of their growing up and being molded by the circumstance.