Not exactly Scotland but a little bit south: Lake District, especially Keswick. Easily accessible by bus or car from Manchester (don't forget to stop and have a look at the Lahun/Kahun sling on display and drink a beer with David), on the countryside with good hicking routes around (e.g. the Skiddaw) and a little lake with shallow shore (and pebble beach ). Beware of the mosquitos.
If you want, I can give you the adress of a good bed and breakfast. I promise, you will go home with more fat on your ribs than you came with

You mean Tennent's, I guess?

take a lot of wet weather gear - particularly in summer it's wet.

They do say that if you can't see more than 10 metres it's raining and if you can see more than ten metres then it's about to start raining

Now I'd personally recommend coming down to the midlands. Better weather, better food and slinging

I suppose i could make it up to the industrial wasteland of manchester if you could only get that far south.

But seriously a 2 year old around scotland in the rainy season (scotland has two seasons: rainy and snowy

Rather you than me

I mean basically scotland has 2 cities and a lot of sheep. Sure the countryside if pretty, when it's not raining.
But as a holiday destination - nah, lol   

Oh yeah nearly forgot. If you're planning on going anywhere near a loch, get some serious heavy duty insect repellant.
The scottish midges are like tiny flying piranha !
Evil nasty bloody things.

Not quite as bad as the blackfly in ontario, but that's not saying much.

One place I would recommend is Stirling Castle. Not only is it famous from Braveheart, it's where the original Unicorn Tapestries were made. They are being remade in medieval fashion. When I was there, they were restoring a hall in hand made period fashion. A piece of William Wallace was supposed to have been buried under there.
  Also, the castle was used as the the model for Hogwarts.
But then, Scottish are known for storytelling.

I am very envious. I would love to see Scotland. Have a safe trip and post lots of pictures please.

weirdly somewhere in scotland ws the hottest place in the country one of the days last week.

So looks like you missed summer