What are you going to do with your kids on a rainy sunday afternoon?

[estobi1]

I am going to visit my brother and his six year old ds this weekend and I have a 2.5 year old dd.

Any ideas what to do with them if it is chucking it down? My brother's flat is quite small, without being rude to him? I have suggested taking them swimming, childsplay kingdom type things (which I always regret the minute I suggest it!). We were thinking of going into London but I don't think I would cope with it (5 months + pg and feeling heavy).

Any ideas would be gratefully received!