Siblings for Darlene Madeline & Theodore Evan?

How about:
Beatrice (Bea)
Josephine (Josie)
Margaret (Maggie)
Winifred (Winnie)
Henrietta / Harriet (Hattie, Hetty, Etta)
Edith (Edie)
Florence (Flora, Flossie)
Mildred / Millicent (Millie, Midge)
Frances (Frankie, Fanny)
Mabel (Mae, Belle)
Agnes (Aggie)
Cecilia (Cece)
Adelaide (Addy, Lady)
Charlotte (Charlie, Lottie)
Eleanor (Ellie)
Genevieve (Gen, Evie)

Bernard (Bernie, Ned)
Edmund / Edward (Ed, Eddie, Ned)
Arthur (Art, Artie)
Wallace (Wally)
Harold (Harry, Hal)
Raymond (Ray)
Frederick (Fred, Freddy)
Sebastian (Seb)
Alfred (Al, Fred, Freddy)
Gordon (Gordy)
Sidney (Sid)
Malcolm (Mal, Mac)
Rupert / Rueben

Hope this helps!