Final answer:
The complete sentence in response to the question is: 'Sí, siempre les digo la verdad a mis padres', which translates to: 'Yes, I always tell the truth to my parents' in English.
Step-by-step explanation:
Yes, the complete sentence in response to the question ¿Siempre les dices la verdad a tus padres? (si) would be: Sí, siempre les digo la verdad a mis padres. This translates to: Yes, I always tell the truth to my parents. In Spanish, 'sí' means 'yes' and 'siempre' means 'always'. The verb 'dices' means 'you tell' and 'digo' means 'I tell'. The phrase 'la verdad' means 'the truth' and 'a tus padres' means 'to your parents'.
Learn more about Truth-telling to parents in Spanish