Kendra Wilkinson wants her son to act as a ''bodyguard'' for her unborn baby daughter.

The former Playboy model, who is expecting her second child with husband Hank Baskett, is trying to encourage her four-year-old son Hank Jr. to look after his younger sibling when she's born into the world in coming weeks.

Speaking to Us Magazine, she explained: ''We're trying to empower him and make him feel like he has a role, like he's a little bodyguard. He's taking it on. Every day it's like, 'I can't wait to teach my sister this!'''

The 28-year-old beauty believes she's developed a closer bond with Hank Jr. since falling pregnant with her second child last year because she wants him to understand that he's got a little baby sister on the way, who is equal to him.

She said: ''Little Hank and I are becoming so much closer. Our hearts are meeting more, we're talking more.

''We want little Hank to understand there's a little girl coming into our lives.''

Kendra recently admitted her second pregnancy has been ''brutal'' but her husband Hank, whom she married in 2009, has been trying to make it easier for her.

She said: ''[He] makes sure my every day is perfect. Like yesterday, he pulled me over, sat me on his leg, and looked me in the eyes and said, 'Kendra you're so beautiful, I know you don't feel it.' I started crying.''