He could face off against his cousin Quade Cooper during the Lions tour with the Reds and Wallabies first five-eighths likely to feature for the hosts.
"We could talk about a rivalry that started at the age of five, when he beat me in a long-distance race,'' Maitland said today. "He's had the wood over me in a few recent battles so hopefully we can get one over him.''
Cooper also tweeted: "Hooooly omg my cousin made the lions!!!! I'm so damn proud of my lil cuz. Came along way from the back yard tokoroa boys with snotty noses!!''
Hartley will feature in his first Lions tour, having made 43 test appearances for England since his debut in 2008. Fellow front rower Vunipola will also make his first Lions tour with nine tests for England under his belt.
The New Zealand-born trio are part of seven Lions squad members who were born outside of the home nations and Ireland. Welshman Toby Faletau was born in Tonga, England's Manu Tuilagi was born in Samoa while Matt Stevens (England) and Ian Evans (Wales) were both born in South Africa.
The Lions begin their tour on June 1 against the Barbarians in Hong Kong before facing the Force in Perth four days later. The opening test against the Wallabies takes place on June 22. New Zealand referee Chris Pollock will be in charge.
- nzherald.co.nz