Is it too late to convince my boys (16mths and 27mths) that they should go and do they toilet bussiness in a set place (behind the shed) in the garden. We have made the area desirable and have put in place a gadget called a, Simple solution Pea Post, Pheromone-treated stake. We have taken the boys to the said place when it is the time they would relieve themselves, but 1: They couldn't care a less about the pheromone stake. 2: They walk into the area, have a sniff of the ground, turn round and sit down looking at us as if to say,"Yeh, what happens nows!?" Instead of relieving themselves they are both holding it in and then when we are playing/relaxing in the garden they will relieve themselves, but anywhere but where we want them to. If we interupt them to try to take them to the set place, they just stop and hold it in again. Is this a lost cause now or do any of you have any suggestions. Thank you.

Have you tried taking them on a lead to this area when you kick them out in the morning for a wee? They should need a wee after holding all night and if their on lead you can control where they go :p  Give treats and praise when they go in this area.