Mrs Spink to be!:
If they don't get an invite I guess they'll take the hint!
i was just thinking the same, MIL2B can give you the addresses but you could 'lose' them or 'forget' to send an invite out, by the time (hopefully) she realises its too late!
i'm quite lucky, i get on quite well with my in laws n both MIL2B n my mum have said they'll help where i ask them to, if i don't ask they won't interfere