9. If It's Not One Thing, It's Your Mother

When Helen and Casey's mother arrives on Nantucket, Helen isn't sure which sister her mother came to see. And when she finds out her mother gambled away the $10,000 for her and Joe's wedding, she is convinced that Casey has always been the favorite of the family. Meanwhile, Fay and Roy split a ticket to a Barbara Streisand concert; Antonio adopts Deedee as his own mother; and Lowell and Brian stuff themselves on Deedee's food in an attempt to see who can out-eat the other.