i have 3 girls and 2 entire males youngest boy is now just over 2 year still does not take much intrest in the girl bits (he was used 8 months ago on my own girl). I always know about a month or so before the older girls are coming in youngest girl only goes 6 months, older 2 girls come in together about every 8 months, but about a month before we have a little bit of swelling and the old boy who is experiances turns into a git, usually after they have eaten or have been let out in the garden or gone for a walk as soon as hes back in the house he is up their backsides and sometimes trying to hump a quick off and he gives up and they will happily settle down, We have this for about a week, then nothing for about 2 weeks then about a week before we actually see colour he starts up again as soon as we see colour hes off on his holiday as he does not cope well with being seperated (he stays with my parents where he is spoilt rotten). The first time this happened i though my girls were having silent seasons now its just become part of the routine.