Small dog - 'whole' - just over a year old.
Big dog - castrated - nearly 10.
Small dog is always trying to get big dog to play. Big dog does play while his patience lasts.
This evening after their walk small dog decided their relationship was ready to go one step further and has been trying to hump big dog all evening. sniffing his bits, washing his ears and generally making a love sick fool of himself.
to complete this picture small dog is a miniature dachshund. Big dog is a large and hairy border collie.
Why?