Dad and little Yvette spend a companionable day cleaning the house, baking a cake, and preparing a birthday party for ``a cat doctor''—a day punctuated with Yvette's eager questions and Dad's patient responses until at last the guest of honor appears. It's Mom, the vet, home from work just in time for the festivities. The simple story is deftly conveyed in natural- sounding dialogue. Trivas's colorful illustrations are lively and freely rendered (sometimes too freely, as in the case of one impossible clockface); with many cozy details, including the amusing antics of the family cats, they nicely reflect this black family's warm pleasure in each other's company. (Picture book. 3- 6)