Complex sentence: In April 1999, Ronaldo married female Brazilian footballer Milene Domingues, at the time pregnant with the couple's first son, Ronald, who was (born in Milan, on 6 April 2000).
Split into simpler sentences: In April 1999, Ronaldo married female Brazilian footballer Milene Domingues, at the time pregnant with the couple's first son, Ronald. The couple had a son, Ronald (born in Milan, on 6 April 2000).