Belgium has moved a step closer to granting same sex couples the right to adopt children. After a heated debate along party lines, parliament narrowly passed a bill overnight to introduce the change.If it wins approval from the Senate in March, the bill passes into law. It would make Belgium the third European Union member to grant homosexual couples equal rights in adoption. The legislation follows the Spanish and Swedish models, allowing gay couples to adopt children of any nationality. Germany, Denmark and the Netherlands currently allow same sex couples to adopt, but with restrictions not applied to heterosexual couples. Gay marriage has been legal in Belgium since 2003. The country’s reputation for progressive lawmaking suggests its latest piece of legislation could get a smooth ride.