So pissed at MIL

Hannah • 20, young mommy to Marlinda and Clarissa, but super happy. Engaged 2-16-17

Just found out she's been diluting bottles when she babysits my daughter. She's been putting 2 scoops of formula which is for 4 oz bottles, into 6 oz bottles. I'm surprised she hasn't gotten sick from water intoxication. She also has been giving her sugar water, plain water with a little sugar in it, in bottles I've specifically told her not to use because they're old and used and my daughter gets sick because they don't have the colic vent in them she's used to. I don't even know what to do anymore. My fiance keeps making me leave my daughter with my MIL for days at a time and seems unconcerned that she's not listening to me. She also was too bothered to grab my daughter's new bottles that she desperately needed because she decided to shop at Wal-Mart and garage sales all day and waited until it was too late. She got a stupid toddler bed for my daughter that she can't even use until she's at least 3 and my daughter is only 7 months. My MIL doesn't listen to me or respect me and it's really irritating I feel like blowing up at her