I'm the proud owner of five gorgeous cockers (2 worker and 3 show), the oldest is 14 and the youngest just 7 months. Overnight, we allow the dogs to sleep where they wish - either on our bed or downstairs - but, just recently, there have been nightly accidents of both the liquid and solid kind for us to clean up on the kitchen floor the following morning. It also happens whilst they are left alone in the mornings and afternoons whilst we are at work - never more than 4 hours at a time. I can understand the younger dogs doing this (Ollie is just a year old) but it seems the older ones are the main culprits. Indeed, both Seb and Jack (14 and 9 years old respectively) have started leaving puddles in the the living room too! Things are getting beyond a joke now and I can't understand why they seem to have reverted to doing things they should have all long-since grown out of. Amber, the only girl, doesn't seem to be following suit so I'm wondering if this could be a male terretorial thing ie 'marking' stuff? The accidents always seem to be in the same particular places. They are always let out in the garden to do their business in the mornings, at lunchtime and last thing at night (aswell as frequently in the evenings) so its not as if they are being forced to cross their legs for any great lngth of time!
Any help, advice, suggestions etc would be most welcome!!

I'm also wondering if the change over to dry food from meat chubs for all except the youngest dog some months ago might be a contributory factor as they do seem to be drinking more water than before