United Kingdom, May 9 -- Olivia Culpo and Christian McCaffrey are expecting their second child together.

The 34-year-old model and the 29-year-old NFL star welcomed their daughter Colette into the world in July and 10 months later, they announced she is set to get a sibling.

Sharing the news on Olivia's 34th birthday, the pair posted a joint Instagram post and wrote: "Best birthday gift. Baby #2 coming soon."

They also posted a carousel of professional pictures, featuring them on a picnic with their daughter and dog.

Olivia wore a long white dress and showed off her sizeable bump, while a strip of sonogram pictures lay on the picnic blanket.

Meanwhile, former Miss USA and Miss Universe winner Olivia - who previously dated Jonas Broth...