After a couple of years a couple wanted to have children...

After a couple of years a couple wanted to have children, but nothing worked. So they went to a doctor, and got checked over. The doctor took time to reassure them. "Don't worry," he said, "Just take this sample bottle home and do the necessary, and bring it back tomorrow." So he went home feeling better, and went back the next day with his little bottle. It was empty. The doctor looked at the bottle carefully, " Problems?" he said. "Have I ever had problems, doc.!" the man replied. " I went home and straight upstairs, and worked at it for over half an hour. Both hands. I tell you doc, my hands got too sore to hold it! I had to get the wife upstairs and she had a go. But even she, with all her experience, couldn't do it. " "So what did you do?" said the doctor. " We had a discussion, and got the mother-in-law involved. I was sure she'd manage it, but it was no go, even when she used her mouth. And doc, she tried with her teeth in, and her teeth out!!" "But nothing we tried would get the top off that bloody bottle!!!!!"