Getting serious... Michelle Williams moves in with boyfriend Jason Segel in New York loft

Actress Michelle Williams has taken her relationship with boyfriend Jason Segel to the next level and moved in with him.

The 32-year-old star of My Week With Marilyn and her daughter Matilda recently began living with Segel in a sprawling New York loft just six months after going public with their romance last April.

A neighbour told the Daily Mail: "Michelle, Jason and Matilda seem very happy here, the building is beautiful. They've been here a few months now and they look right at home."

The couple are living in a stylish property in a converted warehouse with large gates to protect their privacy, not far from their previous home.

Up until recently the actress was still living in the $4.2 million Brooklyn apartment she shared with the late actor Heath Ledger, who is the father of six-year-old Matilda and died of an accidental drugs overdose in 2008.

Matilda is reportedly a huge fan of Jason, who has been friends with Michelle for a long time after being introduced by their mutual friend actress Busy Philips.

A source close to Jason previously said: "I never thought Jason would ever date someone with a kid. But he's taking everything in stride. He's ready to be a grown-up.

"Matilda loves Jason, he knows how to entertain children. You can't be that obsessed with puppets and not learn a few things!"

Meanwhile, Michelle is also said to be smitten by her latest love and friends say she think he could be the one for her.

A pal said: "She's fallen for him hard. She's really giving this a shot."