We'e back from our trip and had an amazing holiday! Thank you for all the suggestions above. Just in case someone searches looking this is what we ended up doing.
We stayed in Newton St Boswells this house
On the first day we walked to St Boswells, went to the Main Street Bookshop and had very lovely cake. We then walked up to Dryburgh Abbey, the muse monument and then walked along the Tweed watching the salmon jumping.
On Monday we went to Jedburgh for the day, we walked past the Abbey, went into Mary Queen of Scots House and then went to the Jail, there's a good children's playground in the town too. On the way back we called into Harestanes which had a good outside play area, nice walks and also a good cafe.
On Tuesday we drove to Edinburgh for the day and went to see the Castle, the national museum and had lunch in the Elephant Cafe.
On wednesday we went to Selkirk, to the Philiphaugh Estate we tried to photograph the slamon jumping but they weren't being compliant! We then went upto into the town and went to Halliwell's House Museum and
Sir Walter Scott?s Courtroom.
Thursday we went to Melrose, where we went in the The Three Hills Roman Heritage Centre, had lunch and then went on the 5 mile roman way walk. This was great as the guide showed you the where the roman forts would have been and gave a very good overview of the area.
Friday we drove over to Lindisfarne (Holy Island), we walked to the castle and Abbey, had lunch and then cross back over and spent nearly 2 hours watching the tide come in, our girls thought this was brilliant!
Saturday, was home time and we called in at Alnwick castle on the way home.
All in all a fab holiday and was amazed by how many of the places we visited had free parking and also free entry into the exhibits.