"Sherlock" stars Benedict Cumberbatch, Martin Freeman and Amanda Abbington
"Sherlock" stars Benedict Cumberbatch, Martin Freeman and Amanda Abbington bbc.co.uk

“Sherlock” season 4 has at least one mystery solved. The show’s titular character (Benedict Cumberbatch) appeared to have posted an announcement of the birth of John and Mary Watson’s (Martin Freeman and Amanda Abbington) baby on a UK paper on Monday, revealing the name of the show’s newest and youngest cast member.

Mild ‘Sherlock’ season 4 spoilers ahead

Premiering on Jan. 1, the fourth season will see John and Mary being parents to Rosamund Mary Watson, according to the print announcement on the Daily Telegraph.

“Congratulations! – To John and Mary Watson on the birth of their beautiful baby daughter, Rosamund Mary Watson. From your friends, Mrs Hudson, Molly and Sherlock, although he hasn’t helped us with this at all as he’s always on the phone,” the text reads.

The infant’s name is the latest revelation in a long line of mysteries for season 4. Fans have been trying to collect – and miss – “blindingly obvious” clues since the third season’s end in 2014 and “The Abominable Bride” special in 2016.

In September, it was revealed that the first and second episodes’ titles would be “The Six Thatchers” and “The Lying Detective” respectively, while the third episode’s title, “The Final Problem,” was revealed just recently.

Read more: ‘Sherlock’ season 4: Episodes 1 and 2 titles revealed

A second and darker trailer for the upcoming season has also been launched, with Toby Jones being featured as the main villain.

Watch ‘Sherlock’ season 4 trailer

As is tradition for the BBC show, “Sherlock” season 4 will have three episodes, starting Jan. 1 and until Jan. 15. It will air on Stan and BBC Worldwide Australia and New Zealand at the same time as the worldwide premiere.

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