Did Kiwi star Melanie Lynskey become a mum?

Melanie Lynskey (L) and Jason Ritter. Photo / Getty Images

Kiwi superstar Melanie Lynskey has reportedly welcomed her first child, with longtime love Jason Ritter.

While the couple have not yet announced anything officially, Us Weekly reports their bundle of joy is at least one month old.

The news comes after director Neema Barnette posted a congratulatory message on social media to the happy couple.

She wrote on December 18: "Congrats to Raising Dion Co Star Jason Ritter & his wife on the birth of their beautiful Sag baby girl. Babies are a blessing & so is Jason!

"What a hands down brilliant talent & exceptional human being he is! I'm blessed to have shared creative energy with you. Thank you for giving me a seamless performance."

A fan of the Kiwi star also tweeted that she saw the pair with a baby at the airport.

"I saw @JasonRitter and @melanielynskey at the airport and I smiled at her and I hope she took that as 'I love you, you've been in so many movies I adore and your baby is adorable,'" she wrote.

Neither of the pair responded but Ritter did 'like' the tweet.