The arrival of a new baby--portrayed with fidelity and feeling, if no imaginative reach. When Mama comes home with his new baby sister, Jason wants so much to be helpful, to be needed, that he keeps saying ""My mama needs me""--to his friends, asking him out to play; to neighbor Mrs. Luby, offering him some ""spicy brown cookies."" Even after he relents and goes to the duck pond with Mr. Pomeroy, the thought that his little sister might awaken sends him home again. But he's discovering that babies sleep a lot; also, was his mama ""that tired when I was born?"" But there comes a chance to help bathe the baby, then a chance to hold her on his lap. And finally, with a hug from his mama (""That's what I needed to do""), Jason is off to play with his friends. The details of baby care, related with tender gravity, keep this from being hackneyed. (So does the compositional variety in Pat Cummings' pictures of the black family.) And the situation is inexhaustible when it is indeed true to life.