In Dickens' David Copperfield, what does Peggotty tell David about Yarmouth?

Peggotty told David that he was going to see her family in Yarmouth and it would be fun, and nothing about his mother's wedding.

Peggotty did not tell David that his mother was getting married; she just told him that it would be fun to visit Yarmouth with him.  Yarmouth was where Peggotty’s family was.  David’s mother wanted Peggotty to take him there so that she could be alone with her new husband, Mr. Murdstone, for a while. 

'Master Davy, how should you like to go along with me and spend a fortnight at my brother's at Yarmouth? Wouldn't that be a treat? … Oh, what an agreeable man he is!' cried Peggotty, holding up her hands. 'Then there's the sea; and the boats and ships; and the fishermen; and the beach; and Am to play with—' (Ch. 2) 

David thinks this sounds good, but he worries about his mother.  Peggotty tells him that his mother has the neighbor and plenty of company.  David doesn’t know what she means, and off they go to visit Peggotty’s colorful family.  This includes Daniel Peggotty, Ham, and little Em’ly, as well as the grumpy Mrs. Gummidge. 

When David returns from this fun little trip, he finds his mother married to the tyrannical Mr. Murdstone.  Murdstone is very controlling, and David’s weakling of a mother cannot stand up to him or his overbearing mother.  Murdstone is soon abusive to David as well. 

‘David,' he said, making his lips thin, by pressing them together, 'if I have an obstinate horse or dog to deal with, what do you think I do?'

'I don't know.'

'I beat him.'

…

'I make him wince, and smart. I say to myself, "I'll conquer that fellow"; and if it were to cost him all the blood he had, I should do it. …’ (Ch. 4)

After beating David, Mr. Murdstone sends him off to a school where they abuse and neglect the boys.  David's mother does not fair much better, and she eventually dies.  Murdstone sends David to work in one of his factories.