Complex sentence: Shortly afterwards, Vella Lovell and Pete Gardner were added as regulars, with Lovell in the role of Heather, Rebecca's underachieving neighbor; and Gardner signed on to replace McDonald in the role of Darryl, Rebecca's new boss.
Split into simpler sentences: Shortly afterwards, Vella Lovell and Pete Gardner were added to the cast. Lovell is set to play the role of Heather, Rebecca's underachieving neighbor; and Gardner has signed on to replace McDonald in the role of Darryl, Rebecca's new boss.