Jessica Chastain has reportedly become a mother via a surrogate

Photos published by Page Six showed the 41-year-old actress carrying the baby in a car seat as she and her husband strolled through New York to a pediatrician's office alongside another woman, who is believed to possibly be their nanny.

And last month, Jessica was seen pushing a stroller in Boston while shooting her upcoming movie 'Eve', fuelling speculation she'd become a parent via surrogacy or adoption as her figure hadn't changed over the last year.

Days after the Boston sighting, Gian Luca, 35, was seen carrying a baby car seat into a hotel with Jessica and her assistant.

The 'Help' actress - who married the fashion ex ecutive last year after five years together - is usually guarded about her personal life but she previously admitted she'd never been interested in tying the knot until she "got to know" Gian Luca.

She previously said: "When I first met my husband, he knew that marriage wasn't something I was interested in.

"And then as we got to know each other, the idea of marriage shifted for me. There are some things worth celebrating -- and he's worth celebrating."

Jessica also admitted she loves the fact Gian Luca is a "gentleman".

She said: "He is a gentleman. And that is very important to me. He's from an old school Italian family. No one in his family's ever been divorced!"