Amanda Seyfried has announced the surprise arrival of her second child - a baby boy.The 34-year-old Mamma Mia! star - who already has a three-year-old daughter Nina with her actor husband Thomas Sadoski - shared a picture of her new son on Instagram after keeping her pregnancy under wraps.Seyfried said: “@thomas_sadoski and I made a little man.”She added in a statement: “Since the birth of our daughter 3 years ago our commitment to the innocent children that are so brutally affected by conflict