I like Jadzea's idea -- get a bed that can acommodate all of you

As for the "experts" opinion on this being not recommended. I say "pshaw" my kids all slept with me for periods in their younger years and they are just fine.

And try not to let it upset you. The thing is the bond between a young child and their mommy is one that is, in a normal situation, very strong. I am sure you care very much for the both of them so try to accomodate as best you can if you can't get a bigger bed.