The actress revealed that filming "love scenes" with Ferrell for the Spanish-language comedy was much more fun than she'd imagined.
"[He] is probably the sweetest, most gentle person I've ever worked with," Rodríguez told Para Todos. "I was so nervous during the love scenes, but Will was always checking up on me."
She added of Ferrell's friendly nature: "He was an absolute dream to work with."
Casa de Mi Padre is the story of a ranch worker (Ferrell) who becomes entangled in a love triangle when his brother (Diego Luna) and his fiancée (Rodríguez) turn up unexpectedly.
The comedy opens on March 16 in the US. A UK release date hasn't been announced.
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Watch a trailer for Casa de Mi Padre below: