Looking like the perfect happy family, lovebirds Reese Witherspoon and Jake Gyllenhaal enjoyed a day out with her children in sunny California.

Reese, 31, and Jake, 27, have been dating for almost a year. Her children, Ava, eight, and four-year-old Deacon have accepted Jake as their new dad and already 'love him to pieces', according to family sources.

'Reese took her time introducing Jake into their lives because she was wary their relationship might end in heartache,' an insider says.

'But before Christmas she knew it was no rebound romance so she's decided to start venturing out in public as a family.'

During the family's New Year's Eve stroll in a Malibu park, Deacon felt so comfortable with his second daddy that he climbed onto Jake's shoulders for a piggyback. Then they had a takeaway lunch from a nearby deli, where Jake grabbed drinks and sandwiches.

'The kids really like their mum's new man,' the insider says. 'He can't replace their real dad, but Jake makes them laugh and devotes a lot of attention to them. It seems to Reese they're thrilled Jake has put the smile back on her face. Although Ava calls him Jake, Deacon gets a bit confused and occasionally calls him "daddy". Reese only corrects him if Deacon is due to see his dad later that day.'

The Oscar-winner, who was married to actor Ryan Phillippe for seven years, kicked Ryan out of their house in 2006 after she discovered he was having an affair with his Aussie Stop Loss co-star Abbie Cornish. Ryan, 33, and Abbie, 25, went public with their romance following his official divorce a few weeks ago.

Reese and Jake fell in love filming Rendition and they recently took a step closer to marriage when he gave her a 'fidelity' ring as a token of his devotion.

‘Reese can't believe she's lucky enough to have found love again so quickly,' the insider says. ‘Although she's decided she's not going to wait too long before marrying again, she's not rushing into anything right now.

'But she really loves Jake, and her friends expect them to be engaged by June. The fact she's even talking about having his child one day shows how serious she is.'

Jake, a diehard fan of baseball's Boston Red Sox, gave Reese a hat as a symbol that the couple who loves the same team loves each other too. Reese, once a fan of Ryan's favourite team, the Philadelphia Phillies, has been wearing it ever since.

Ryan was said to be devastated and declared he didn't want his son wearing one.

'The baseball hat was just a reason for Ryan to vent his anger,' the insider says.

'In fact, he's really upset that Jake has become like a second dad to his kids. Ryan is going through every young divorced dad's worst nightmare - he's battling to stay a part of his kids' lives right now and remain a meaningful part of their future.'

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