Ryan Reynolds slips up as he refers to 'daughter' in tweet

Ryan Reynolds appears to have revealed he and wife Blake Lively have had a second daughter.

The 39-year-old actor and his former Gossip Girl star spouse welcomed the baby at a hospital in Manhattan, New York, in September (16).

Since then, Blake and Ryan have remained quiet on details about their new arrival, but the Deadpool actor seemed to have slipped up in a message posted on his Twitter page on Friday (21Oct16).

"The mobile above my daughter's crib is just a whole bunch of NuvaRings (birth control method). So she remembers how lucky she is," Ryan tweeted.

Fans were quick to respond, with many taking the tweet as a confirmation of the baby's gender.

It's not the first time a Hollywood star has appeared to accidentally reveal their child's sex. During an appearance on the Today show earlier this month (Oct16), Ashton Kutcher dropped the news that wife Mila Kunis is expecting a baby boy.

"She points to Mila and she's like, 'baby brother' when she points to the belly, and then she points to dad and she goes, 'beer'," he said. "So I think she gets there's something in the belly, but I don't quite think that she knows that it's not going to be a plastic doll yet."

Ryan and Blake are also parents to daughter James, who will turn two in December (16).

The news of Blake's pregnancy first surfaced in April (16), and she debuted her growing baby bump at the world premiere of her Woody Allen film Cafe Society at the Cannes Film Festival in France in May (16).

Blake and Ryan have made no secret of their desire to have a big family.

"I'm one of five kids; my husband's one of four," Blake explained during an interview on breakfast show Today in June (16), before joking, "We're officially breeders! You can go on our website and we will give you some of our children."

The couple wed in 2012.