Q&A: Imagine no possessions...

Continuing with the sibling theme, Jen writes:

"Our daughter Natalie will be almost 2 1/2when our second child is born this fall, and I'm getting pretty worried about dealing with jealousy.  I'm specifically concerned about possessiveness related to THINGS - mostly baby gear, maybe clothes & diapers - because we plan to hand down everything we can, given our limited budget.  In the past few months, when friends have come to visit and their children have used some of her outgrown gear (booster seat, Moses basket, blankets) she's been INSANELY possessive.  She is in a big disequilibrium phase right now, and has been for about 4 months, so she should be better when the baby is born... but heading downhill again when the baby is about 3 months - prime time to be starting to play with toys, and moving into "her" stroller, Ergo, etc., etc.

Natalie is very sweet with the children, bringing them small toys and playing with them, but she goes ballistic when they use her stuff.  We had dinner with friends last weekend, and she would not calm down about the baby using her booster high chair - demanding it was her turn, that we take the baby out, warning the baby she had "one minute" left, etc.  We told her she could sit in it when the baby was done, but she kept talking and talking about it the whole time.  It did not make for an enjoyable dinner.  She doesn't show her frustration physically, at least with small babies, but did bite her babysitting buddy (spends at least 2 days a week with him; he's 4 months younger) once when he crawled into the Moses basket that she was playing with (which had been left out from a baby visiting the night before).  I think in a weird way the digital age is compounding the issue - she has seen many pictures of herself as an infant using all of these things and so still feels a strong connection to them even though she's long since outgrown them.

We're not having her give up her crib - the baby will sleep in our room for the foreseeable future - and there are a few other things she won't have to share, but most baby things will naturally be reused.  I do also hope to/plan to tandem nurse, so she won't have to yield the boobs entirely to her sibling.

We're reading a lot to Natalie about babies, and she is very excited about the baby.  She tries to share some things with the baby even now - she will wear a sticker for a few minutes and then put it on my stomach "for the baby".  She likes to sing and talk to the baby.  I think she will be fine overall in the end.  My partner has read Siblings without Rivalry, and it's in my (gargantuan) stack of things to read.  My partner says it's mostly focused on older kids, anyway.  But I envision the scenes when the baby is really here, and taking up some of our time as well as HER things... and I get pretty worried.

Is this one of those grit our teeth and get through it things, or is there something we can do about it?"

Is there any way you can do a hard sell to convince her she's a Big Girl who does Big Girl Things and has Big Girl Toys and Possessions and get her to buy it so thoroughly that she doesn't even care about that Baby Stuff anymore? That's pretty much all I've got. I have no idea how to mediate between a toddler and a baby (and seem to be failing Mediation for Mothers 202: Preschooler to Elementary Schooler for the last week or two, too).

Somebody help, because all I've got in my bag of tricks is manipulation marketing.