DD1 was a bit older (just turned 3) but we did alot of prep as i just assumed that she would be there, i had my mum down to look after her and give her attention or take her to the playground if needed.
we read "hello baby" (the HB one, not the baby animal one lol). we also screened a few youtube videos of birth where other kids were present (a good one is linked on here somehwere...i'll try and find it!).
DD1 coped really really well. she was just plain excited :) she was a good helper in rubbing my back and then helped DH in pumping up the birth pool. it was super cute! when i got into full labour-land mum took her next door for a playdate. i was really bummed though as i was happy to have her around and in the end she missed the actual birth bit by 30 seconds...happened much quicker than we thought it would.
This time i will have a good neighbour friend around to help with the girls. i am a bit more concerned with DD2 as she is younger like your DS and when she wants me, she *really* wants me. but i am hoping that the neighbour being here and playing with her will be enough...that and i dont plan on being in labour long :ROFL:
but also, TBH i was having such a fun time, that i loved sharing it with DD1, and i really hope to be able to do that this time too...i was able to read stories and potter around in the garden etc. it's part of the awesomeness of having baby at home, there is no need to rush or think about packing up and heading off...it really changes the perspective and stress ITMS.

