No biju it is not easy, well first time if you go to get return visa in airport immigration, you need photocopy of passports(yours and depd.)fill the form and pay 500qrs for each.If they have already completed 6 months out side Qatar then first confirm air tkt and show them so they will give you enough time. If they intend to cross 6 months you will be given full 6 months more to stay out side of Qatar.
Next time it will be very hard and after twice, you make it(return visa) they may refuse.