First grand baby.....Third baby shower??

My daughter is expecting in about one month. She has had two baby showers already-one from her mom-in-law and the second from her work. She has just about everything she needs for the baby. In fact she has two car seats, two strollers, two types of swings, crib, changing table, dresser, hugh ortment of clothes, lots of diapers, you name it-she has it! I have been planning a shower for her but I am stumped if I should do a diaper theme or somthing else. I am very excited for my first grandchild...her name will be Stevie...and very happy for my daughter that she has received so many items for the baby's layette. Please help give a new grandmom-to-be some good advice for a wonderful baby shower.