Bristol decided to have baby as revenge for mom Sarah Palin's pregnancy

London, Sept 13 (ANI): Levi Johnston has claimed in his new tell-all book that ex-flame Bristol decided to have a baby as revenge for her mother Sarah Palin's pregnancy.

In "Deer in the Headlights," Johnston says Bristol, daughter of ex-Alaska Gov. Sarah Palin, convinced him to get her pregnant so she could have a baby in revenge for her mother's surprise pregnancy with son Trig, reports the Sun.

When Bristol found out her mother was pregnant she was angry, he claims in the book, and said she should be the one having a baby - not her politician mom.

"Let's get pregnant," Bristol told Johnston, the hockey-playing hunk claims.

Johnston says he went along with the idea because he knew "it's what she wanted" and because he was "too dumb" to use protection. (ANI)