Hi I've namechanged as this will out me!
It's my MILs 70th birthday soon and she's decided she'd like to spend it in London. We live in the home counties, her other son lives in Kent and she's from up North. She'll be bringing her partner who we've only met a few times.
There will be 6 adults and 3 children 4, 8 and 10.
So far we have booked a boat trip from London Eye to Greenwich. She is happy to spend the day in Greenwich but we'll have to have an early dinner near Waterloo to get the youngest child home to bed.
We are on quite a tight budget but want her to have a nice day. Any ideas of what we could do during the day, for lunch and places for dinner? I am in dread of it raining for the whole day so if we plan a picnic it all goes to pot 
Thank you for any suggestions, we are going round in circles!