Buster and Tess portrait-nearly there

The portrait of Buster and Tess is tantalisingly close to completion now,after a weekend spent away from the board running my drawing workshop i got back to this drawing yesterday and spent almost the whole day completing tess's ear.there are a myriad of layers of graphite applied here to build up the shape and form before adding the fur details and being so close to completion i now have to take my time and resist the temptation to rush to the 'finishing line' thus un-doing all my good work so far.All that remains to be done is to complete the neck of the dog and then go over the whole piece with subtle tone adjustments here and there until it all gels nicely