Complex sentence: Crofts was born an only child in Sao Paulo, Brazil, where his mother, Jeanne Crofts, was working as a dancer in a Circus known as Circo Tihany.
Split into simpler sentences: Crofts was born an only child in Sao Paulo, Brazil. His mother, Jeanne Crofts, was working as a dancer in Sao Paulo for a Circus known as Circo Tihany.