My daughter is about to turn 6 months old, & from the day she was born she’s been using slow flow nipples because the NICU nurses said it wouldn’t confuse her as much when I go to breastfeed her. Well after we got home I gave up on breastfeeding (got PPD) & I just kept her with the slow flow nipples. A close family friend I’ve deemed adopted grandma gave her a Tommee Tippie transition cup with handles. It’s supposed to transition them to a sippy cup better. It comes with a bottle nipple & a sippy cup style nipples. Both are medium flows & I cannot find replacement nipples any slower than medium for this cup. How do you increase the nipple flow safely? I gave her the cup this morning with 2 ounces of formula in it with the bottle nipple & most of it was leaking from her mouth than she actually got.