SB 7.5.46

vartamāno ’vidūre vai
 bālo ’py ajaḍa-dhīr ayam
na vismarati me ’nāryaṁ
 śunaḥ śepa iva prabhuḥ
Synonyms: 
vartamānaḥ — being situated; avidūre — not very far away; vai — indeed; bālaḥ — a mere child; api — although; ajaḍa-dhīḥ — complete fearlessness; ayam — this; na — not; vismarati — forgets; me — my; anāryam — misbehavior; śunaḥ śepaḥ — the curved tail of a dog; iva — exactly like; prabhuḥ — being able or potent.
Translation: 
Although he is very near to me and is merely a child, he is situated in complete fearlessness. He resembles a dog’s curved tail, which can never be straightened, because he never forgets my misbehavior and his connection with his master, Lord Viṣṇu.
Purport: 

The word śunaḥ means “of a dog,” and śepa means “tail.” The example is ordinary. However one may try to straighten a dog’s tail, it is never straight but always curved. Śunaḥ śepa is also the name of the second son of Ajīgarta. He was sold to Hariścandra, but he later took shelter of Viśvāmitra, Hariścandra’s enemy, and never left his side.