If you're bored... help me plan what to wear!

I decided to do a Mommy & Me Mother's Day studio mini session... the photographer is using the backgroup pictured below. Need to get some photos with the two of us - the only ones I have that I am in are from her newborn session! It's only a 30-min session, so I imagine just one outfit for each of us... or maybe 2 for her, one for me.

A lot of my clothes still don't fit (due to an extra 5 lbs and bf'ing boobs)... I have a cute navy dress I could wear or I could go causal with jeans and either an aqua or ivory lace blouse... or I could be convinced to buy something new (though I should save $ if I can). J is probably set. She has 4 dresses to choose from (see below) - a solid yellow ruffly one (fits her best), a purply/pink/white one, a pink/aqua/yellow/ivory print, and an aqua one (below).

Thoughts? Would it be too matchy with the background if I wear aqua and she wears yellow, for instance? Would a navy dress look okay?

Can you tell I'm indecisive?!

(more pale in person and needs to be ironed)