I think your thoughts on it being pregnancy related might be right. I'm a childminder and have worked with children for about 11years. If you don't mind me suggesting afew things... This is what other parents and myself have done with my mindees.
Firstly (which I'm sure you've done already) reassure your existing child that they are loved and are special, that u will still make time for them, things will change but they will be included.
Second, sometimes making a "baby box" together helps them feel involved, allowing them to choose afew little presents for baby practical things like dummies, wipes, cream, rattles, then maybe go through their old baby things with them, see of they'd like baby to have an old rattle or teddy of theirs? As it will be more special for baby knowing big bro or sis has given it, and will make the older child feel proud and bond with baby abit.
Sitting together looking through older child's baby things and photos, discussing what baby may look like aswell as reminiscing over how lovely and special they were and still are.
Involving big one in some of the minor decisions may help them feel involved and important too.
Maybe a mummy date once a month, just you and oldest. Special time just you two.
Also have you mentioned to her teacher as they may have some ideas that I've missed, or have ideas more specific to your child as they know her?
Hope this helps. I know its not the same, but my fulltime mindee has been overly sensitive and challenging in her behaviour since finding out too. I'm going to try some of these ideas myself, as I love my mindees very much and want them to be confident and assured in that. Xx
It breaks my heart seeing her cry over everything do you mommies know how long this will last? Yesterday she was crying and I asked her why and all she said was I don't know... I even cried with her!
Yes. My son is doing the exact same. He crys over everything . He has a two year old sister and she doesn't even do it like he does.
My daughter is the same way I figured that maybe it because I might be having a boy maybe? I don't know