Complex sentence: When Downing left the series in 1990, the part was taken over by Debra Lawrance who played the character from 1990--1998, after Debra took over the role the character of Pippa was awarded a fictitious OAM For her services as a foster parent.
Split into simpler sentences: When Downing left the series in 1990, the part was taken over by Debra Lawrance who played the character from 1990 to 1998. After Debra took over the role, the character of Pippa was awarded a fictitious OAM for her services as a foster parent.