The possessive forms are Trevor's and Lesley's; or Trevor and Lesley's. Examples: Trevor's and Lesley's houses are on this block. Trevor and Lesley's house is on this block.
LESLEY
Lesley Salisbury's birth name is Lesley Brown.
Lesley Byers's birth name is Lesley Picchietti.
Lesley Manville is 5' 2".
Lesley Stahl's birth name is Lesley Rene Stahl.
Lesley Sheridan's birth name is Lesley-Anne Johnson.
Lesley Rion's birth name is Lesley Jane Rion.
Lesley Nagy's birth name is Lesley Lynn Nagy.
Lesley Gore's birth name is Lesley Sue Goldstein.
Lesley Visser's birth name is Lesley Candace Visser.
Lesley Gaither's birth name is Lesley DeAnne Carson.