cross my heart (and hope to die)

US /krɔs maɪ hɑrt (ænd hoʊp tu daɪ)/
UK /krɔs maɪ hɑrt (ænd hoʊp tu daɪ)/
"cross my heart (and hope to die)" picture
1.

juro de pés juntos, juro

used to emphasize that one is telling the truth or making a sincere promise

:
I promise I won't tell anyone, cross my heart.
Eu prometo que não contarei a ninguém, juro de pés juntos.
He said he'd be there on time, cross his heart and hope to die.
Ele disse que estaria lá a tempo, juro de pés juntos e espero morrer.