Complex sentence: His two sons, Ferdinand the Younger (1828-1857) and Henri de Braekeleer (1840-1888) followed in their fathers footsteps and also became painters; but also his nephew, Adriaan Ferdinand de Braekeleer (1818-1904), was a painter.
Split into simpler sentences: His two sons, Ferdinand the Younger (1828-1857) and Henri de Braekeleer (1840-1888) followed in their father's footsteps and also became painters. His nephew, Adriaan Ferdinand de Braekeleer (1818-1904), was also a painter.