Poyo is acting as a surrogate mother for the orphaned kittens, while the Saito’s search for adopters.  But spending time with Poyo, each kitten is developing a unique trait.
They all developed a 
fondness for round things.
A todos les encantan las cosas redondas.
Todos adoran las cosas redondas.
Todos eles desenvolveram um
gosto por coisas redondas.