Saoirse Ronan dating ‘Mary Queen of Scots’ co-star Jack Lowden

According to Page Six, Saoirse Ronan is dating her “Mary Queen of Scots” co-star Jack Lowden

They looked extremely close at the after-party for their new movie Tuesday night

A movie source told Page Six of Ronan and Jack: “We don’t know when they got together, we only found out on Tuesday night when they rolled up together — but they seem very happy and sweet.”