You know your pregnancy is going to be just fine when your unborn baby gives you the thumbs up.

The expectant mother of twins had a routine ultrasound done last week and what one of her unborn babies did during the ultrasound has the internet talking. In the picture it appears as if one of the twins is giving a 'thumbs up'.

Dubbed the "Fonzie Fetus" -- named after the thumbs up character Arthur Fonzarelli from the TV show Happy Days -- the twins are due in January and the sex of the twins is not known yet, but the expectant parents will find out soon.