Don proposes calling his and Rosie’s baby “Bud,” for “Baby Under Development” (34) and because of the word’s association with flowering. This label reflects his logical approach, as babies “flower” from zygote to embryo to fetus to baby. Rosie resists technical terms, but accepts the image of a bud as poetic. The couple’s agreement to this label is one of few in The Rosie Effect, symbolizing how the baby will further connect them. As for Don alone, his Bud diagram is altered to reflect the baby’s size and shape at each week of gestation, indicating his attachment. While Bud is still a concept to him, he endeavors to understand this concept on his own terms. As Bud develops, he adds more tiles to his bathroom-office diagram, indicating the baby’s ever-growing presence in his mind. In the end, the diagram proves Don’s parental love to Rosie.

When Don moves him and Rosie into George’s beer apartment, the place unsurprisingly smells of beer. This smell serves as a running joke about human adaptability, as the couple grows accustomed to it. This lingering also serves as a metaphor and warning about the forces seeking to separate the couple, such as Rosie’s studies and Don’s research on fatherhood—the latter’s methodical nature being what interested George in the first place.