"The hard, sad Miss Furnivall, and the cold Mrs. Stark, looked pleased when she came fluttering in like a bird, playing and pranking hither and thither, with a continual murmur, and pretty prattle of gladness...."See in text(The Old Nurse's Story)
Hester’s description of toddler Rosamond recalls a chattering bird, bringing cheerfulness and conversation to previously silent and darkened places. Rosamond’s good humor serves as a contrast to Mrs. Stark and Miss Furnivall, who are both quiet and unfriendly. Note also that birds are notoriously fragile creatures; Hester’s protectiveness of Rosamond is shown in her word choice to describe the child.
"a face as full of fine wrinkles as if they had been drawn all over it with a needle's point...."See in text(The Old Nurse's Story)
Notice the simile here: Miss Furnivall’s wrinkles are so precise that it looks as if someone has carefully drawn them on with a pinpoint. This highlights both her advanced age and suggests she is someone who is as precise as her appearance.
"who was like a sunbeam in any family, be it never so grand..."See in text(The Old Nurse's Story)
Notice the simile used to characterize Rosamond: she is like a “sunbeam,” a bright flash of warm, comforting light in an otherwise dreary landscape. Hester calls Rosamond her “pet” out of affection, not out of condescending ownership, showing the true bond that exists between the two.